Jeju Island In Korea Research Articles

Effects of Storm Waves Caused by Typhoon Bolaven (1215) on Korean Coast: A Comparative Analysis with Deepwater Design Waves

This paper employs the third-generation simulating waves nearshore (SWAN) ocean wave model to estimate and analyze storm waves induced by Typhoon Bolaven, focusing on its impact along the west coast and Jeju Island of Korea. Utilizing reanalyzed meteorological data from the Japan Meteorological Agency meso scale model (JMA-MSM), the study simulated storm waves from Typhoon Bolaven, which maintained its intensity up to high latitudes as it approached the Korean Peninsula in 2012. Validation of the SWAN model against observed wave data demonstrated a strong correlation, particularly in regions where wind speeds exceeded 20 m/s and wave heights surpassed 5 m. Results indicate significant storm wave heights across Jeju Island and Korea's west and southwest seas, with coastal grid points near islands recording storm wave heights exceeding 90% of the 50-year return period design wave heights. Notably, specific grid points near islands in the northern West Sea and southwest Jeju Island estimated storm wave heights at 90.22% and 91.48% of the design values, respectively. The paper highlights the increased uncertainty and vulnerability in coastal disaster predictions due to event-driven typhoons and emphasizes the need for enhanced accuracy and speed in typhoon wave predictions amid the escalating climate crisis.

Connectivity between sea turtles off Jeju Island on the Korean Peninsula, and other populations in the western Pacific

The northwestern Pacific region is an important habitat for sea turtles, hosting five species out of seven. There is still limited information available about the sea turtle aggregations around the Korean Peninsula, which is the northern boundary for many sea turtle species in the western Pacific area. The present study aims to investigate the migratory route of sea turtles visiting Jeju Island. Five species of sea turtles were identified from by-catch and stranding data between 2013 and 2022 on Jeju Island in Korea: green (Chelonia mydas; 24 individuals), loggerhead (Caretta caretta; 9), hawksbill (Eretmochelys imbricata; 2), olive ridley (Lepidochelys olivacea; 2), and leatherback (Dermochelys coriacea; 1). Mixed stock analysis using mitochondrial DNA haplotypes revealed that Jeju green turtles primarily originate from the rookeries of the Japanese Archipelago. This connectivity between two regions was also supported by the similar genetic composition of loggerhead turtles. Similarly, satellite tracking data showed that several green turtles originating from Jeju Island migrated to waters near the Ryukyu Archipelago in Japan. Nevertheless, about 60% of the tracked green turtles stayed near Jeju Island, with most overwintering there, indicating the long residency in Jeju Island. This study also provides the genetic sequences of other three species including new orphan haplotypes of hawksbill and olive ridley turtles. Our findings suggest that Jeju Island serves as a stable foraging habitat and provide insight into understanding the habitat range of sea turtles in the western Pacific.

ISCNT embryo culture system for restoration of Cervus nippon hortulorum, presumed to be sika deer in the Korean Peninsula.

Sika deer inhabiting South Korea became extinct when the last individual was captured on Jeju Island in Korea in 1920 owing to the Japanese seawater relief business, but it is believed that the same subspecies (Cervus nippon hortulorum) inhabits North Korea and the Russian Primorskaya state. In our study, mt-DNA was used to analyze the genetic resources of sika deer in the vicinity of the Korean Peninsula to restore the extinct species of continental deer on the Korean Peninsula. In addition, iSCNT was performed using cells to analyze the potential for restoration of extinct species. The somatic cells of sika deer came from tissues of individuals presumed to be Korean Peninsula sika deer inhabiting the neighboring areas of the Primorskaya state and North Korea. After sequencing 5 deer samples through mt-DNA isolation and PCR, BLAST analysis showed high matching rates for Cervus nippon hortulorum. This shows that the sika deer found near the Russian Primorsky Territory, inhabiting the region adjacent to the Korean Peninsula, can be classified as a subspecies of Cervus nippon hortulorum. The method for producing cloned embryos for species restoration confirmed that iSCNT-embryos developed smoothly when using porcine oocytes. In addition, the stimulation of endometrial cells and progesterone in the IVC system expanded the blastocyst cavity and enabled stable development of energy metabolism and morphological changes in the blastocyst. Our results confirmed that the individual presumed to be a continental deer in the Korean Peninsula had the same genotype as Cervus nippon hortulorum, and securing the individual's cell-line could restore the species through replication and produce a stable iSCNT embryo.

An Implication of Cannibalism Motif in “the Myth of Seolmundae-halmang” of Korea

"Cannibalism" is widely regarded as an absolute taboo for cultivated humanity. Not only does the bare citation of the word" cannibalism" and encountering images about this subject make utmost people extremely uncomfortable. Nonetheless, the “ cannibal motif ” exists in humanities folk literature, and why is it being repeated in modern literature, media, and culture? If humanity can achieve a sense of spiritual satisfaction or there's a universal idea that desperately wishes to partake through such a horrifying motif, what kind of content can it be? When trying to address this curiosity, there's an interesting text which is worth noting. It's “ the myth of Seolmundae- halmang( Grandma Seolmundae) ”, which is being passed down on South Korea's Jeju Island. Seolmundae- halmang was worshipped as the creator goddess of Jeju Island, yet in the stories about her death, she's eaten by her own sons. Why did this goddess have to experience such a terrible death? Also, if “ myth ” contains motifs of universal human life, what was the content that Jeju Island's mythology group wanted to share through the death and devouring of the goddess? To find answers to these questions, several former studies on the conception of cannibalism were examined, thereby the aspects of cannibalism that was in human life was verified. As a result, the cannibalistic motif of this myth confirmed that the endo-cannibalism concept of the primordial mythology enthusiasts group was the result of the divine succession process from Seolmundae-halmang to her sons. Furthermore, when interpreted in the context of symbolism for human reality, it is also revealed that children who have grown up at the expense of their parents have embodied the universal and realworld principle of human life in which they realized their parent's sacrifices and inherited their lives. The significance of such research results can be recognized for investigating the mythological meaning and value of cannibalistic elements of the Seolmundae-halmang myth. This allowed us to reveal the meaning and value of one of Korea's major mythological materials more fully, as well as confirm the universal value of Korea's mythological materials.

Identification of Late Ripening Citrus Mutant, Ara-unshiu (Citrus unshiu), and Its Selectable Marker.

'Miyagawa-wase' mandarin (Citrus unshiu Marc. cv. Miyagawa-wase early) is one of the most widely cultivated citrus varieties on Jeju Island in Korea. Mutation breeding is a useful tool for the induction of genetic diversity for the rapid creation of new plant variants. We previously reported the use of gamma irradiation for the development of new citrus varieties. Here, we report a new mutant, Ara-unshiu, with a unique late fruit ripening phenotype. We investigated the fruit morphological characteristics including weight, vertical/transverse diameter, peel thickness, hardness, and color difference, as well as sugar and acid contents of the Ara-unshiu compared to wild-type controls. We then used whole genome re-sequencing and functional annotation by gene ontology to identify and characterize single nucleotide polymorphism (SNP) and insertion/deletion (InDel) variants in the Ara-unshiu, finding a greater abundance of annotated genes containing InDels compared to SNPs. Finally, we used allele-specific PCR to identify molecular markers among the homozygous SNPs detected from the Ara-unshiu genome sequencing. We report a primer set that effectively distinguishes the Ara-unshiu from the wild-type control and other citrus varieties. Our findings provide insights into the mechanisms controlling the timing of fruit ripening and tools for the molecular breeding of citrus varieties.

Tutorial on time series prediction using 1D-CNN and BiLSTM: A case example of peak electricity demand and system marginal price prediction

Although research on time series prediction based on deep learning is being actively carried out in various industries, deep learning technology still has a high entry barrier for researchers who have not majored in computer science. This paper presents a tutorial on time series prediction using a deep learning-based model. The entire process of time series data prediction is presented—from data collection to evaluation of prediction results. The details of each step are shown through a case example of predicting peak electricity demand and system marginal price of Jeju Island in Korea using the 1D-CNN and BiLSTM model. In Jeju Island, the proportion of renewable energy in the total power generation capacity is increased to 67% in 2021, requiring more accurate electricity demand forecasts. Therefore, using 808 days of training data from February 2018, electricity demand and SMP for the next 21 days were predicted. To make it easier for readers to follow, the example uses only open public data, and the entire Python source code is shared via a GitHub repository. The prediction error calculated by WRMSSE showed 0.42 in electricity demand and 0.63 in SMP max. A WRMSSE value less than one means that the forecast was relatively good, that is, better than naïve forecasting. This tutorial is not limited to the energy industry but can be utilized for any application requiring time-series data prediction. This article is expected to be of great help to researchers who need to understand the process of time series prediction using deep learning and use it for application in their industry.

Early Holocene dietary patterns on the Neolithic Jeju Island, South Korea: Evidence from stone tools and stable carbon isotope analysis

This study investigates Neolithic subsistence on Jeju Island in Korea during the Early Holocene. Gosanri, our main site, provides evidence of the Early Holocene peopling to the Island by 10,000 cal. BP with pottery making tradition, while the Neolithic sites appeared in the Korean peninsula only 2000 years later. Gosanri and most of the Early Holocene sites, collectively called the Incipient Neolithic (10,000–8000 cal. BP), are located along the coastal lines of Jeju, and thus Incipient Neolithic people were assumed to conduct marine-based subsistence activities. This assumption has not been tested partly as most sites did not preserve any organic remains that can reflect diet. We examine this unanswered question by providing direct evidence on diet through the compound specific isotope analysis on pottery and by examining the stone tool compositions for procuring food. Our analyses suggest that Early Holocene islanders relied on terrestrial resource substantially. The proximity to the coast is not a self-sufficient evidence for the assumption of marine-oriented diet. Instead, the seasonality of food resources, the seasonal climate fluctuation, and the locational merit to a quarry, all equally affected Jeju islanders’ diet preference and subsistence practice. Overall Gosanri provides another convincing case of the broad-spectrum resource use to the transition to the Early Holocene.

Matricide, Myth, and the Great Mother: An Asian Ecofeminist Reading of Seolmundae (the Creator of Jeju Island in Korea) and Nüwa (the Protector Goddess of Chinese Mythology)

Abstract This study is an Asian ecofeminist reading of two Great Mother Goddesses, Seolmundae (the Creator of Jeju Island in Korea) and Nüwa (the Protector Goddess of Chinese mythology). Nüwa (yin) cannot be reduced to just a counter part of Fuxi (yang) while Seolmundae cannot be shadowed as one of many other creation myths. Rather, they are the Great Mother, the Divine Feminine as the fecundity of Life, the healing Spirit, and the caring Heart which we have to discover and rescue from our forgotten histories to transform violent culture into caring and healing culture. The purpose of this study is to say yes to salim (enlivening, healing, caring-Life with a capital L) and to say no to disruptions of Life (war, violence, destroying nature) as we witness the physical and spiritual sufferings and degradation caused by oppression of those that rendered subaltern. Discovering the Goddess is our ethical imperative for expanding healing culture and loving nature and recognizing the agencies/subjectivities of the subaltern, including Asian women and nature.

Influence of Foam generated in Pharmaceutical Suspensions Manufacturing Process on Active Pharmaceutical Ingredient Contents of Finished Products

Ficus erecta var. sieboldii (Miq.) King is a deciduous tree distributed on Jeju Island in Korea. The beneficial effects of F. erecta var. sieboldii have been noted in many diseases such as nephritis and arthritis. However, it is still unclear how F. erecta var. sieboldii modulates the immune response in mice; therefore, this study aimed to assess whether F. erecta var. sieboldii extracts upregulate this immune response. The administration of F. erecta var. sieboldii increased the spleen index, splenocytes proliferation, and serum tumor necrosis factor (TNF-α) and interleukin (IL)-6 levels. In addition, F. erecta var. sieboldii also increased the messenger ribonucleic acid (mRNA) expression of helper T cell-related cytokines (TNF-α, IL-6, IFN-γ, IL-17, and IL-10) and transcription factors (T-bet, RORγt, and Foxp3) in the spleen. These results suggest that F. erecta var. sieboldii can regulate the immune response in mice.

풍력발전기를 고려한 복합전력계통에서의 신뢰도 평가에 관한 연구

In this paper, the probabilistic reliability evaluation algorithm in terms of probabilistic supply adequacy according to the system input of wind turbine generator(WTG) previously proposed by this research team is presented in more detail for a composite power system that also considers the transmission system, and furthermore, the usefulness of the application is verified. In this study, the method was presented in detail through a sample case that can be done manually. Additionally, based on the proposed methodology, a model system similar to the system size of Jeju Island in Korea was assumed, and the reliability evaluation of the composite power system(HL II) considering a large number of WTG in the actual power system size was simulated in various ways, and its usefulness was shown in this paper. Finally, as an application example, the utility of the method developed in this study was verified by showing the possibility in terms of probabilistic reliability of the transmission system expansion planning, which has recently been emphasized more in importance. Therefore, it is expected that the method presented in this study will be practically usable for obtaining the optimal scenario in terms of probabilistic reliability evaluation when conducted the probabilistic transmission system expansion plan considering multiple WTGs.

Effect of Ficus erecta var. sieboldii (Miq.) King Leaf Extracts on Mice Immune cell Activation

Ficus erecta var. sieboldii (Miq.) King is a deciduous tree distributed on Jeju Island in Korea. The beneficial effects of F. erecta var. sieboldii have been noted in many diseases such as nephritis and arthritis. However, it is still unclear how F. erecta var. sieboldii modulates the immune response in mice; therefore, this study aimed to assess whether F. erecta var. sieboldii extracts upregulate this immune response. The administration of F. erecta var. sieboldii increased the spleen index, splenocytes proliferation, and serum tumor necrosis factor (TNF-α) and interleukin (IL)-6 levels. In addition, F. erecta var. sieboldii also increased the messenger ribonucleic acid (mRNA) expression of helper T cell-related cytokines (TNF-α, IL-6, IFN-γ, IL-17, and IL-10) and transcription factors (T-bet, RORγt, and Foxp3) in the spleen. These results suggest that F. erecta var. sieboldii can regulate the immune response in mice.

Anti-varicella zoster virus and related anti-inflammation effects of ethanolic extract of Elaeocarpus sylvestris

Ethnopharmacological relevanceElaeocarpus sylvestris var. ellipticus (ES), a plant that grows in Taiwan, Japan, and Jeju Island in Korea. ES root bark, known as “sanduyoung,” has long been used in traditional oriental medicine. ES is also traditionally used to treat anxiety, asthma, arthritis, stress, depression, palpitation, nerve pain, epilepsy, migraine, hypertension, liver diseases, diabetes, and malaria. However, lack of efficacy and mechanism studies on ES. Aim of the studyIn the present study, we aim to investigate the VZV-antiviral efficacy, pain suppression, and the anti-inflammatory and antipyretic effects of ES. Methodsand methods: Inhibition of VZV was evaluated by hollow fiber assays. Analgesic and antipyretic experiments were conducted using ICR mice and SD Rats, and anti-inflammatory experiments were conducted using Raw264.7 cells. ResultsTo evaluate the efficacy of ESE against VZV, we conducted antiviral tests. ESE inhibited cell death by disrupting virus and gene expression related to invasion and replication. In addition, ESE suppressed the pain response as measured by writhing and formalin tests and suppressed LPS-induced inflammatory fever. Further, ESE inhibited the phosphorylation of IκB and NF-κB in LPS-induced Raw264.7 cells and expression of COX-2, iNOS, IL-1β, IL-6, and TNF-α. ConclusionE. sylvestris shows potential as a source of medicine. ESE had a direct effect on VZV and an inhibitory effect on the pain and inflammation caused by VZV infection.

A new species of Trichoglossum (Geoglossales, Ascomycota) from South Korea

Herein, a new species of the genus Trichoglossum is described. The new species named as T. jejuense was collected from Jeju Island in Korea. It is distinguished from other Trichoglossum species by thick, 8-spored asci and 15–16 septate ascospores. Phylogenetic analyses of the internal transcribed spacer of ribosomal RNA and morphological characteristics suggest that T. jejuense is a distinct species.

Contribution of TV Dramas and Movies in Strengthening Sustainable Tourism

This study aims to (a) identify the relationship between travel motivation and popular media (mainly films or TV programs), (b) examine the relationship between destination images and popular media as an information source, and (c) investigate the influence of popular media on destination’s decision-making process. The relationship is focused on three aspects: motivation, destination image, and the decision-making process for tourists. This study employed a self-administered questionnaire survey. The questionnaire was composed of (i) respondents’ motivation and general information about their visit to the destination (Jeju Island in Korea), (ii) attributes of the film-induced tourism of their visit to the destination, and (iii) respondents’ socio-demographic elements. A correlation analysis and a standard multiple regression analysis were employed. The results discovered that there is a significant relationship (a) between a destination and popular media, (b) between destination image and popular media, and (c) between the decision-making process and popular media. The implications of this study can help destination marketers and managers build competitive strategies using the effective management of film-related tourist attraction sites to increase visitor numbers and ensure that a sustainable long-term relationship is encouraged between destinations and tourists.

Electric vehicle charging management using location-based incentives for reducing renewable energy curtailment considering the distribution system

There have recently been an increasing number of variable renewable energy curtailment cases to manage power system stability problems caused by the overproduction of variable renewable energy. Variable renewable energy curtailment can be a factor that hinders the development of the power industry by reducing the economic viability of variable renewable energy operators and the efficiency of energy use. In this study, an economic curtailment methodology using electric vehicles to mitigate energy waste and economic losses is proposed. Charging point operators participate in incentive-based demand response programs with their charging station loads under curtailment situations. A location-based incentive algorithm considering distribution system constraints is proposed to avoid distribution system congestion. A response model based on random arrival electric vehicles considering demand and price elasticity, time pressure, and charging pressure is developed. The proposed methodology is verified through case studies based on the environment of Jeju Island in Korea. The case study results show that the proposed methodology can use energy more economically and effectively than conventional variable renewable energy curtailment methodology.

Tourists’ preference on the combination of travel modes under Mobility-as-a-Service environment

This study explores a tourists’ preference for tour mode bundle, defined as a set of preferable travel modes for multiple trips in a tour, under Mobility-as-a-Service (MaaS). In the context of tourism, MaaS could improve transportation sustainability by providing integrated information about sustainable transportation modes. To develop a systematic understanding of tourists’ preference for tour mode bundle, we design a tour-based stated preference (SP) choice experiment based on bundle configuration of travel modes in MaaS including a shared van as a paratransit mode in combination with the existing bus and taxi services. A web-based SP survey is conducted for 331 individuals who visited Jeju Island in Korea. Two mixed logit models are estimated to reveal differences between the trip- and tour-based mode choice situations. The estimation results reveal that the trip sequence significantly influences the preference for travel mode in a tour mode bundle, which has significant cross effects with individual and travel context attributes. A shared van is the most preferred in both a trip and a tour. Persistence to using the same mode and synergy of using different modes are captured through significant cross effects of sequence-specific travel modes in a tour mode bundle. Based on these findings that can only be identified through tour-based choice situations, MaaS can be more effectively designed in tourism.

Estimating the Temporal Distribution of Groundwater Recharge by Using the Transient Water Table Fluctuation Method and Watershed Hydrologic Model

HighlightsThe transient water table fluctuation method (TWTFM) is revisited.A novel application of linking SWAT model and TWTFM is suggested.A method is proposed to estimate daily groundwater recharge distribution.The method is demonstrated for the Jeju Island in Korea.Abstract. Estimating groundwater recharge remains a difficult but necessary task as part of managing available groundwater supplies. For example, the average groundwater recharge rate of Jeju Island is 54%, which is considerably higher than the inland recharge rate (~15%) in Korea. Although groundwater is the main water source of this and many other islands, quantifying temporal groundwater recharge for water resources planning remains difficult. To estimate groundwater recharge based on rainfall, a simple and straightforward method is proposed that uses an application of the Transient Water Table Fluctuation Method (TWTFM) linked with the Soil and Water Assessment Tool (SWAT). By using the computed annual percolation from the SWAT as input, two parameters (reaction factor and specific yield) could be estimated by assuming that the sum of daily recharge via the TWTFM was approximately equal to the annual percolation near the water table. This methodology was applied to the Hancheon watershed of Jeju Island, South Korea. Runoff time series data for two years (2009 and 2010) were used to calibrate SWAT and another two years of data were used to validate computed discharges from SWAT. For the calibration of the combined SWAT and TWTFM model, groundwater level data from 2009 and 2010 were used, and then data from 2011 and 2012 were used to predict groundwater recharge using the calibrated TWTFM parameters. The proposed methodology can be used as an efficient tool for estimating the temporal distribution of groundwater recharge using only groundwater data and the annual percolation rate. This methodology can be beneficial for regions where the vadose zone depth is deeply formed and temporal recharge predictions are essential for water management. Keywords: Reaction factor, Specific yield, SWAT, Transient water table fluctuation method (TWTFM).

Study of the independent gametophytes found on Jeju Island in South Korea and the first record of the obligate independent gametophyte of Antrophyum obovatum Baker.

Fern gametophytes have often been neglected in research; however, studies on gametophytes are crucial for a better understanding of the evolution of ferns. During their life cycle, some gametophytes produce large and long‐lived populations without producing sporophytes and reproduce independently through asexual means, such as through the formation of gemmae.In this study, we investigated independent gametophytes on the Jeju Island of Korea, which was located on the land bridge between East China and Japan during the glacial periods. Fourteen gametophyte populations were collected from seven sites, of which 13 populations were clearly identified as belonging to four fern species known to occur in Jeju Island with BLAST searches using rbcL and trnL‐F sequences.Surprisingly, the last remaining population constituted undescribed taxa in Korea. We presented the first report of the independent gametophytes of Antrophyum obovatum Baker which has not been previously recorded in Korea. It has been supposed that many ferns sought suitable habitat throughout the land bridge between China and Japan. However, Jeju Island might be unsuitable for vittarioid ferns that prefer a tropical or subtropical environment. Consequently, only two species of vittariod ferns (A. obovatum and Haplopteris flexuosa (Fée) E.H. Crane) in the form of a gametophyte and sporophyte, respectively, exist on Jeju Island. Therefore, this gametophyte population must be protected and managed from a conservation perspective.In the case of the independent gametophyte of Hymenophyllum wrightii Bosch, haplotype analysis was conducted based on the rbcL sequences and the result supported that the North American populations were migrated from Japan through land bridge during the glacial periods and Jeju populations were recently established by long‐distance dispersal of the Japanese populations.

Biochemical Characterization of an Extracellular Xylanase from Aestuariibacter sp. PX-1 Newly Isolated from the Coastal Seawater of Jeju Island in Korea

Biochemical Characterization of an Extracellular Xylanase from Aestuariibacter sp. PX-1 Newly Isolated from the Coastal Seawater of Jeju Island in Korea

Human Intangible Cultural Contents and City Branding: Haenyeo of Jeju Island in Korea and Perfumer of Grasse in France

Human Intangible Cultural Contents and City Branding: Haenyeo of Jeju Island in Korea and Perfumer of Grasse in France