• Journal of the Korean Society of Marine Environment & Safety
• /
• v.4 no.2
• /
• pp.69-83
• /
• 1998

Sea transportation has long been a vital component of the transport systems of the world. The great majority of imports and exports to and enlarge their national merchant marines. This effort is meant partly to arrest earlier trends of having their trade carried by ships from outside the region and partly to promote regional integration and improve the national balance of payments. However, sea transportation has been exposed to various types of threats on the high seas, in coastal waters and in port areas. Piracy is any robbery or other violent action, for private ends and without authorization by public authority, committed on the seas. Because piracy has been regarded as an offense against the law of nations, the public vessels of any state have been permitted to seize a pirate ship, to bring it into port, to try the crew(regardless of their nationality or domicile), and, if found guilty, to punish them and to confiscate the ship. Piracy has occurred in all stages of maritime history. The increased size of merchant vessels, the improved naval patrolling of most ocean highways, the regular administration of most islands and land areas of the world, and the general recognition by governments of piracy as an international offense resulted in a great decline in piracy in the 19th and 20th centuries. Piracy has, however, occurred in the 20th century, and the practice of hijacking ships has developed into a new form of piracy. The number of incidents of sea piracy against ships reported was 229 in 1997. Since 1991, 1,051 such acts have been reported. The purpose of this research is to examine the origin and development of the piracy to understand the current situation of such violence on the seas. In addition, what should be done by international community will be presented to prevent the piracy in the future.

• Journal of Internet Computing and Services
• /
• v.2 no.4
• /
• pp.101-109
• /
• 2001

In recent year, the use of digital picture information and general picture information has been increased, However, numerous copyright infringement and pirate copy of picture information through Internet and CD-ROM happen very often, As a result, several methods of watermarking have been presented to solve and verify distortion of the original data, In addition, watermark data have been suggested to resolve the vastness of the original data, Watermarking methods are often used to protect the right of ownership of a copyright, However, these Watermarking methods have brought the obscurity of recognition caused by the complexity of verification procedure and the increase of magnitude computation occurrence, This paper mainly mentions about the local optimization of scaling parameter, the maximization of hiding of Watermark information and maximization of watermark information in case of restoration that determine the amount of inserted information which is used for preventing distortion and transformation of the original data caused by insertion and hiding of Watermark information on compounding Autostereogram into JPEG picture information.

• Korean journal of applied entomology
• /
• v.40 no.3
• /
• pp.253-258
• /
• 2001

Biological control of thrips with Orius strigicollis Poppius was evaluated in a hot pepper greenhouse. To study the biological control strategy of thrips on hot pepper grown in greenhouse, three plots were established: natural enemy removed plot(CNT), pesticide treated plot(PAT) and O. strigicollis released plot with no pesticide application (NRT). The nymphs of O. strigicollis were found on the leaves of lower stratum in CNT and NRT at 13 days after the first release. The density of thrips was suddenly dropped and maintained at low level since 15 day after transplanting in NRT. The densities of thrips on hot pepper flowers was also maintained at much less level in NRT than in CNT. The thrips and O. strigicollis, which were aggregated in flowers, may have resulted in improved predator searching. Average damage indices of CNT, PAT and NRT were 0.31, 0.05 and 0.08 and the percentage of damaged fruit were 80.0, 17.1 and 24.8% respectively. The damage index and percentage of damaged fruit of NRT was slightly higher than PAT, but very lower than CNT. The introduction of the adults of O. strigicollis, which was the biological control agent for the control of thrips, was effective on hot pepper.

• Korean journal of applied entomology
• /
• v.23 no.3 s.60
• /
• pp.166-171
• /
• 1984

The present studies were conducted to investigate the relative toxicity of several insecticides to the rice insect pests and the predatious spider, Pirate subpiraticus. In laboratory test by topical application, BPMC and MIPC for the plant and leafhoppers were toxic to Nilaparvata lugens, but less toxic to Pirata subpiraticus. Other carbamate insecticides such as carbaryl, carbofuran, and MTMC showed highly toxic effect on P. subpiraticus as well as N. lugens. No organophosphates showed selective toxicity to P. subpiraticus. Thiocyclam, effective to Chilo suppressalis and Sesamia inferens, had highly good selective toxicity to P. subpiraticus. In case of insecticides for Nephotettix cincticeps, BPMC only had a little selective toxicity between N. cincticeps and P. subpiraticus. Organophosphate insecticides which had been reported to induce chemical resistance to N. cincticeps showed high $LD_{50}$ value to N. cincticeps. In pot trials, dust formulation was more toxic to P. subpiraticus than emulsifiable concentrate. It was more toxic to P. subpiraticus to increase number. of insecticide application.

• Korean journal of applied entomology
• /
• v.15 no.2 s.27
• /
• pp.89-93
• /
• 1976

The present report is dealt with the spiders which are caught within a space of $1m^2$ of rice paddy field where was harvested the rice crops in Jeonbug district, from November 4 to 11, to 1975. 1. Twenty-one species of spiders were caught at the area during the period. Of these the dominant species were Gnathonarium dentatum, Pirate subpiraticus, Gnathonarium gibberum, Oedothorax insecticeps etc. 2. Average density of spiders within a space of $1m^2$ of rice paddy field where rice crops was harvested was as follows: 125 at Iri, 102 at Jinan, 133 at Buan, and 58 at Daejang. 3. The scientific names of spiders which were caught in rice paddy field for the first time in Korea were Gnathonarium gibberum, Enoplognatha japonica, Erigone prominens, Erigonidium graminicola, Theridion octomaculatum, Lycosa pseudoannulata, Dolomedes angustivirgatus. As the result of this survey, fifty-five species of spiders were recorded in rice paddy field of Korea.

• Korean journal of applied entomology
• /
• v.18 no.3 s.40
• /
• pp.137-141
• /
• 1979

The distribution of spiders on paddy Holds in the suburbs of Kwangju city and the seasonal fluetuation of their population were surveyed for two years from November 1975 to November 1977. The results obtained are summarized as fallows: 1. The total number of species of the spiders on paddy fields collected in Kwangju area was 38 which belong to 24 genera and 13 families. Out of these 16 species were already known to exist in this area, and two other species were those known to occur in Korea. The remaining 22 species were new collections among which Cornicularia vulgaris 01 was the one with no record of collection in Korea. 2. The spiders on paddy fields collected in this area were mostly those belonging to two families i.e. Erigonidae and Lycosidae, and predominating species were Gnathenarium dantatum(WJDER) and Oedothorax insecticeps BOES. et STR. 3. The population density was highest in November just before wintering and lowest in March and April after wintering and an intermediate peak in July and August.

• The Journal of Society for e-Business Studies
• /
• v.23 no.3
• /
• pp.85-109
• /
• 2018

The rapid development of information and communication technology has made it for people to pirate digital contents easily and quickly. Although many studies have investigated the underlying factors that lead to an individual engaging in digital piracy, few studies have provided holistic and integrative view on this issue. Therefore, this study attempts to build integrative research model based on theory of planned behavior (TPB), norm activation model (NAM), and habit. For this purpose, this study develops nine hypotheses that explain the relationship between attitude, personal norm, habit, and behavioral intention, and tests them with survey data collected from 337 participants. The results of this study show that attitude, perceived behavioral control, personal norm, and habit have impact on behavioral intention of digital piracy while subjective norm does not affect behavioral intention. This study contributes to expand existing studies by identifying the relationship between attitude, personal norm, habit and behavioral intention.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.22 no.6
• /
• pp.1231-1242
• /
• 2012

Traitor tracing schemes deter traitors from sharing their private keys by tracing at least one of the subscribers who were implicated in the construction of a pirate decoder. In general, it is assumed that the system manager in the scheme generates and distributes the subscribers' private key. But if the system manager knows the subscribers' private keys, he cannot convince a third party of a certain subscriber's piracy. To solve this problem, the system manager should not know the whole parts of subscribers' private keys and this leads to researches of asymmetric schemes. Moreover for the purpose of enhancing subscribers' privacy, there were two proposals of introducing anonymity onto asymmetric traitor tracing schemes, but one of them turned out to be a failure. In this paper, we point out that the other proposal also has flaws. We consider how to introduce anonymity to traitor tracing schemes, as a result, we suggest a new framework which is practical. We also construct a scheme by using an anonymous credential system and an asymmetric traitor tracing scheme. We prove the security of our scheme and consider the typical applications.

• Maritime Security
• /
• v.1 no.1
• /
• pp.175-214
• /
• 2020

Previous studies cannot effectively explain the rise of piracy in Somalia and NIgeria. First, there is a lack of explanation for the process that from a small maritime robbery into a org anized pirate g roup. Second, it is difficult to explain the low level of piracy in countries with extreamly poor conditions, from Somalia to Nigeria. In this study, I argue that the more severe foreign countries infringe on economic maritime sovereignty in vulnerable countries, the higher the intensity and frequency of piracy. If the infringement of economic maritime sovereignty caused by foreign groups occurs in a fragile state, the government could not respond to the acts of foreign groups, resulting in increased damage to maritime people, deteriorating the regional economic situation. As hostility grows, a culture favorable to piracy is created, which is actively utilized by local forces to inspire the people's hostility, and a favorable environment for piracy emerges in a way that responds politically to foreign powers. In Somalia and Nigeria, the infringement of economic maritime sovereignty by foreign groups emerged severe. And based on the stagnation of the local economy and hostility toward foreign groups, favorable conditions were formed for piracy, resulting in the rise of piracy. Meanwhile, Somalia's neighbor, one of the most fragile states in the world, Yemen have not suffered piracy. Also, the foreign infringement to the maritime economic sovereignty has rarely been observed.

• Korean Journal of Remote Sensing
• /
• v.39 no.5_3
• /
• pp.909-919
• /
• 2023

Benthic marine invertebrates, the invertebrates living on the bottom of the ocean, are an essential component of the marine ecosystem, but excessive reproduction of invertebrate grazers or pirate creatures can cause damage to the coastal fishery ecosystem. In this study, we compared and evaluated You Only Look Once Version 7 (YOLOv7), the most widely used deep learning model for real-time object detection, and detection tansformer (DETR), a transformer-based model, using underwater images for benthic marine invertebratesin the coasts of South Korea. YOLOv7 showed a mean average precision at 0.5 (mAP@0.5) of 0.899, and DETR showed an mAP@0.5 of 0.862, which implies that YOLOv7 is more appropriate for object detection of various sizes. This is because YOLOv7 generates the bounding boxes at multiple scales that can help detect small objects. Both models had a processing speed of more than 30 frames persecond (FPS),so it is expected that real-time object detection from the images provided by divers and underwater drones will be possible. The proposed method can be used to prevent and restore damage to coastal fisheries ecosystems, such as rescuing invertebrate grazers and creating sea forests to prevent ocean desertification.