• Korean Journal of Plant Resources
• /
• v.36 no.5
• /
• pp.469-489
• /
• 2023

Six field surveys were conducted at 29 locations from April 2020 to April 2022 to identify the freshwater flora of the Taean Peninsula. Based on the collected specimens, the vascular plants of the Taean Peninsula were summarized as 391 taxa: 94 families, 248 genera, 362 species, 5 subspecies, and 24 varieties. Freshwater plants in the Taean Peninsula consisted of 104 taxa, 45 taxa for aquatic plants, and 59 taxa for wetland plants. When classified by life history, annuals accounted for 33 taxa, winter annuals 5 taxa, biennial 6 taxa, and perennials accounted for most of the 60 taxa. Among the 391 identified taxa, 2 taxa of Endangered plants, 3 taxa of Korean endemic plants, 5 taxa of IUCN red list plants, 49 taxa of Korean floristic target plants, 38 taxa of biological resources subject to the approval of outbound transfer, 55 taxa alien plants and 7 taxa of ecosystem disturbing plant. The results of this study are intended to be used as basic data on the freshwater environment and distribution of aquatic plants in the Taean Peninsula.

• Explosives and Blasting
• /
• v.41 no.3
• /
• pp.13-25
• /
• 2023

The conventional bench blasting method uses the bottom initiation in all blast holes in a round, whereas the MDS (mixture detonation system) method applies the bottom and top initiations alternately according to the spatial position or temporal sequence of each blast hole. The former and latter are respectively called the SMDS (spatial MDS) and TMDS (temporal MDS) methods. Another variant called MMDS (modified MDS) is designed for the specific use in the site having a fly-rock problem. This study compares the MDS method to the conventional method in the aspect of rock fracturing effect. The comparison is made by numerical simulations for a two-row bench blasting model in the LS-DYNA. The SPH-FEM coupling method is utilized for constructing the blasting model. The SPH elements are used for the rock in the near-field region of the blast holes, and the FEM elements for that in the far-field region. The RHT material model is used for the rock. As a result of the simulations, it was found that up to 0.4 m deeper damaged zone was appeared in the SMDS method than in the conventional method for the case of the burden 1.6 m and bench height 3.0 m. In addition, the fly-rock velocity to the normal direction of the bench slope was appeared about 2.0 m/s lower in the MMDS method compared to the other methods.

• Journal of Industrial Convergence
• /
• v.21 no.9
• /
• pp.41-48
• /
• 2023

Recently, there has been a sharp increase in the damages caused by ransomware across various sectors of society, including individuals, businesses, and nations. Ransomware is a malicious software that infiltrates user computer systems, encrypts important files, and demands a ransom in exchange for restoring access to the files. Due to its diverse and sophisticated attack techniques, ransomware is more challenging to detect than other types of malware, and its impact is significant. Therefore, there is a critical need for accurate detection and mitigation methods. To achieve precise ransomware detection, an inference engine of a detection system must possess knowledge of ransomware features. In this paper, we propose a model to extract and classify the characteristics of ransomware for accurate detection of ransomware, calculate the similarity of the extracted characteristics, reduce the dimension of the characteristics, group the reduced characteristics, and classify the characteristics of ransomware into attack tools, inflow paths, installation files, command and control, executable files, acquisition rights, circumvention techniques, collected information, leakage techniques, and state changes of the target system. The classified characteristics were applied to the existing ransomware to prove the validity of the classification, and later, if the inference engine learned using this classification technique is installed in the detection system, most of the newly emerging and variant ransomware can be detected.

• Journal of Industrial Convergence
• /
• v.21 no.12
• /
• pp.55-62
• /
• 2023

Recent ransomware attacks employ various techniques and pathways, posing significant challenges in early detection and defense. Consequently, the scale of damage is continually growing. This paper introduces a machine learning-based approach for effective ransomware detection by focusing on file encryption and encryption patterns, which are pivotal functionalities utilized by ransomware. Ransomware is identified by analyzing password behavior and encryption patterns, making it possible to detect specific ransomware variants and new types of ransomware, thereby mitigating ransomware attacks effectively. The proposed machine learning-based encryption behavior detection technique extracts encryption and encryption pattern characteristics and trains them using a machine learning classifier. The final outcome is an ensemble of results from two classifiers. The classifier plays a key role in determining the presence or absence of ransomware, leading to enhanced accuracy. The proposed technique is implemented using the numpy, pandas, and Python's Scikit-Learn library. Evaluation indicators reveal an average accuracy of 94%, precision of 95%, recall rate of 93%, and an F1 score of 95%. These performance results validate the feasibility of ransomware detection through encryption behavior analysis, and further research is encouraged to enhance the technique for proactive ransomware detection.

• Korean Journal of Plant Resources
• /
• v.37 no.2
• /
• pp.171-202
• /
• 2024

If the plant genetic resources and information-sharing systems held by arboretums worldwide are effectively utilized, it is believed that a conservation system for plant diversity in the currently inaccessible North Korean region could be established. This study was conducted to review the scientific names of plants native to North Korea but not to South Korea and to assess the status of genetic resources held in domestic and international arboretums. To compile a list and status of North Korean plant's genetic resources, updated checklists of vascular plants in Korean Peninsula and online plant information databases were consulted to compile synonym, distribution range, and other related information. A total of 486 taxa (449 species, 13 subspecies, 21 varieties, 1 forma and 2 hybrids) from 236 genera and 64 families, representing 12.34% of the total native flora of the Korean Peninsular were presented in the North Korea plant list, and the presence of rare, endemic and northern lineage species was confirmed. It was found that 384 taxa from 190 genera, 53 families of North Korean plants are held as genetic resources in 333 arboretums and plant research institutions across 46 countries and 5 continents worldwide. This study is expected to contribute to the construction and application of a species list for plants native to the Korean Peninsula.

• Korean Journal of Environment and Ecology
• /
• v.38 no.1
• /
• pp.1-21
• /
• 2024

This study conducted surveys to identify the distribution of communities and flora according to vegetation in the coastal sand dunes of Sagye in Jeju Special Self-Governing Province, located at the southernmost tip of Korea. The survey was conducted over 20 sessions from April 2020 to October 2021. As a result of the study, physiognomy was classified into six correlated vegetation types: plant communities on the salt marsh, annual communities on a coastal drift-line, herb communities on a dune, shrub communities on a coastal dune, forest-edge communities on a dune, and artificial afforestation vegetation. The survey identified 43 communities, and a total of 212 taxa were found to be distributed among 62 families, 166 genera, 191 species, 15 varieties, 3 subspecies, and 3 forma. It was found that there were five rare plant taxa distributed in the area, including the Cymbidium macrorrhizum which was classified as an endangered Class II plant by the Ministry of Environment. Floristic target species identified by the surveys included 2 taxa for grade V, 5 taxa for grade IV, 15 taxa for grade III, 14 taxa for grade II, and 19 taxa for grade I. Climate-sensitive biological indicator species included 11 indicator and 2 candidate species, representing a high ratio of 33.3% of all indicator species and 15.4% of candidate species. Naturalized plants included 16 families, 43 genera, and 52 taxa, with a naturalization rate of 21.1% and an urbanization index of 24.5%. It is expected that these results will be widely used as data needed to prepare conservation and management measures for biodiversity in response to climate change in coastal dunes in the future.

• Korean Journal of Environment and Ecology
• /
• v.38 no.1
• /
• pp.22-47
• /
• 2024

This study aims to reveal the distribution of native plants, rare plants, and specialty plants and provides basic data for efficient ecosystem management through a survey of the flora in Mt. Chijae (Gamagol) and its adjacent areas in Damyang-gun, Jeonnam-do, while also identifying useful plants in the eco-city Damyang-gun for distinctive garden plants. A total of 21 field surveys were conducted from March 2022 to June 2023 to collect and identify 492 taxa consisting of 101 families, 304 genera, 444 species, 10 subspecies, 35 varieties, and 3 formas. The analysis of the prepared sample list showed 14 taxa designated as specialty plants, 9 taxa designated as rare plants by the Korea Forest Service, 7 taxa designated as the national red (i.e., endangered) plants by the Ministry of Environment, and 68 taxa with phylogenetic specific species, of which 45 taxa for Grade I, 5 taxa for Grade II, 16 taxa for Grade III, and 2 taxa for Grade IV were confirmed. The list included 155 taxa of biological resources subject to export approval by the Ministry of Environment and 38 taxa of alien plants of which 7.7 percent were naturalized, and the urbanization index was 6.1 percent. Four taxa were ecosystem-disturbing invasive alien plants designated by the Ministry of Environment introduced artificially or naturally from abroad. This study is expected to contribute to creating unique and attractive landscapes in Damyang if the specific plants found in Mt. Chijae are grown and planted in city gardens.

• Korean Journal of Heritage: History & Science
• /
• v.57 no.1
• /
• pp.38-51
• /
• 2024

Although the bottle gourd (Lagenaria siceraria) is a crop with a cultivation history of about 10,000 years in the Old and New Worlds, archaeological considerations on the cultivation and use of bottle gourds on the Korean Peninsula are extremely rare. Accordingly, we reviewed previous reports on bottle gourds and examined the morphological characteristics of seeds and rind fragments from the Korean Peninsula. The investigation yielded several conclusions. First, bottle gourd cultivation likely began during the Bronze Age alongside the introduction of so-called southern crops. Evidence suggests that bottle gourd remains were more prevalent during the Three-Kingdoms period, indicating its significance as a crop during the historical era. Second, bottle gourd seeds from the Three-Kingdoms period exhibit characteristics of both African and Asian subspecies, showcasing a high level of morphological diversity. Third, rind thickness indicates that bottle gourds found at the Bongseon-ri site were of varieties with large fruits. Taken together, it is concluded that the bottle gourd was introduced to the Korean Peninsula during the Bronze Age, and people cultivated a range of bottle gourd varieties during the Three-Kingdoms period.

• Korean Journal of Environmental Biology
• /
• v.42 no.1
• /
• pp.28-45
• /
• 2024

This study was conducted to investigate the flora of Sonjukdo Island(Yeosu-si), Korea. From results of four field surveys from April 2023 to October 2023, we identified 483 total taxa, representing 440 species, seven subspecies, 35 varieties, and one hybrid. They were placed in 322 genera and 109 families, including 249 taxa newly recorded in this study. Among them, four taxa were endemic to Korea, four taxa were IUCN red list plants, and 22 taxa were climate sensitive indicator plants. Floristic target plants amounted to 99 taxa, including two taxa of grade IV, 41 taxa of grade III, 10 taxa of grade II, and 46 taxa of grade I. A total of 54 taxa of alien plants were identified, with a Naturalized Index of 11.2% and an Urbanization Index of 13.8%. Three plants disturbed the ecosystem. The flora of this surveyed area belongs to the south-coast province among floral provinces of the Korean Peninsula. Our results provide basic data on vascular plants flora, plant species diversity, and distributional changes.

• Korean Journal of Environmental Biology
• /
• v.42 no.1
• /
• pp.95-126
• /
• 2024

In this study, we investigated the vertical distribution and vascular plants on Joryeongsan Mountain in Baekdudaegan, Korea. The results of four field surveys from April to September 2023 identified a total of 552 taxa, representing 491 species, ten subspecies, 43 varieties, six forms, and two hybrids in 314 genera and 101 families. The elevational distribution ranges of 360 taxa of vascular plants were also identified. Among them, 19 taxa were endemic to Korea, and two taxa were rare plants. The floristic target plants amounted to 100 taxa, specifically two taxa of grade V, seven taxa of grade IV, 25 taxa of grade III, 33 taxa of grade II, and 33 taxa of grade I. Seventy-eight taxa were northern lineage plants. In all, 29 taxa of alien plants were recorded in the investigated area, with a naturalized index of 5.3% and an urbanization index of 7.4%. Two plants disturbed the ecosystem. Species richness along the elevation showed a reversed double-hump shape with peaks at low, mid, and high elevations. The results of a cluster analysis showed a high degree of similarity between adjacent elevation sections, except in lowlands. Detrended Correspondence Analysis ordination also supported distinct groups by elevation. Warmth index values ranged from 62.1℃·month to 92.9℃·month on Joryeongsan Mountain. Our results provide primary data on vascular plants and valuable information on the current distribution ranges of plant species on Joryeongsan Mountain. These data could serve as a baseline for comparing species shifts at elevations under future climate changes.