• Korean Journal of Ecology and Environment
• /
• v.51 no.1
• /
• pp.71-85
• /
• 2018

A recent topic of interest within ecology is ecosystem services that are importantly connected with biodiversity. Biodiversity is a fundamental component of ecological studies and has been the subject of many studies worldwide. However, studies on the diversity and distribution of freshwater fish were not undertaken in earnest until 2000, and the number of internationally available studies is therefore still limited. In this study, we used data from "The Survey and Evaluation of Aquatic Ecosystem Health (hereafter SEAEH)" within the framework of which whole water systems on the Korean peninsula are annually monitored to investigate and determine the current status of the diversity and distribution of freshwater fish, as well as to elucidate major factors impacting freshwater fish. A total of 130 species from 28 families were identified at around 953 sites in the SEAEH investigation of 2014. The species Zacco platypus (relative abundance: 28.2%) and Z. koreanus (19.3%) were identified as the most abundant species on the Korean peninsula, and besides these 20 endangered species, 51 endemic species and 4 exotic species were also collected. Highest (96 species) and lowest (72 species) diversity were identified in the Han River Watershed and the Yeongsan/Seomjin River Watershed, respectively. The mean endemic rate was 32.7%, which is higher than the previous rate determined in 1995. The exotic species Micropterus salmoides, Lepomis macrochirus and Carassius cuvieri were found in the whole river system except north Yeongdong, whereas Oreochromis niloticus occurred only at three sites due to the cold water temperatures in winter. Totally, 28 species were found to be translocated to different water systems not connected with known original habitats, most translocations occurring in the Nakdong River and the Yeongdong region. Among the translocated species, Opsariichthys uncirostris amurensis, and Erythroculter erythropterus were dominantly distributed in the mid- to lower reaches of Nakdong River where they may be harmful to the native fish assemblages due to their strong predation. The construction of weirs in connection with the "4 River Project" generated changes in fish assemblages before, during and after the project, resulting in altered habitat condition. Especially, a decrease in the number of endemic species and an increase in the abundance of lentic species were seen. Human-induced global warming will allow exotic species requiring high water temperatures to adapt to the environmental conditions of the Korean peninsula, which may enhance the diversity of native fishes and create changes in distribution. For the establishment of realistic and efficient management and protection strategies for Korean freshwater fish, SEAEH, which produces fundamental and quantitative data for Korean streams, is an important and necessary tool.

• Korean journal of applied entomology
• /
• v.55 no.4
• /
• pp.329-336
• /
• 2016

Occurrence of oriental corn borer, Ostrinia furnacalis, and yield in a paddy-upland rotation field for 8 maize (Eolrukchal 1, Heugjeom 2, Miheukchal, Ilmichal, Heukjinjuchal, Chalok 4, Mibaek 2, Daehakchal) and 7 sorghum (Hwanggeumchal, Anzunbaengisusu, Moktaksusu, Sodamchal, DS-202, Nampungchal, Donganme) varieties has been surveyed. In a monitoring study using a pheromone trap carried out from 15 May to 10 September, the density of O. furnacalis adults increased rapidly from about 2 weeks after maize planting and reached the highest density at mid June. After that, their density was fluctuated a little at earlier September. The number of the damaged maize and invasive pores on the stem of 2 maizes and sorghum varieties was examined. The mean number of the damaged maize per 20 plants was 19 and 18 plants, and the number of invasive pores was 1.8 and 1.4 per maize stem in Daehakchal and Mibaek 2, respectively. In a survey carried out at harvest period using 8 maize varieties, the damaged ratio was 94%, 92%, 71%, 64%, 54%, 52%, and 45% in Daehakchal, Mibaek 2, Ilmichal, Eolrukchal 1, Chalok 4, Miheukchal, and Heugjeom 2, respectively. The number of invasive pore per Ilmichal stem was 1.4 and that of the others was less than 1.0 per stem. In addition, the damaged ratio of maize ears was 50% in Ilmichal, 40% in Heukjinjuchal, 37% in Daehakchal, etc. The damage pattern of 2 sorghum varieties, Nampungchal and Donganme, by O. furnacalis larvae was steeply increased from planting to 2 months and the trend was continued up to earlier August. At this time, the mean number of damaged sorghum was 13 and 9.2 plants for Nampungchal and Donganme, and the number of invasive stem pores was 1.06 and 0.46, respectively. In another survey carried out at harvest period for 7 sorghum varieties, their damaged ratio was 95% in DS-202, 76% in Moktaksusu, 75% in Sodamchal, 67% in Nampungchal, 57% in Anzunbaengisusu, 46% in Donganme, and 34% in Hwanggeumchal. The damage of sorghum varieties was much higher and severer than that of maizes by O. furnacalis larvae. The number of invasive pores on a sorghum stem was 1.7 in DS-202, 1.4 in Moktaksusu, 1.3 in Sodamchal, 1.1 in Nampungchal, 1.0 in Anzunbaengisusu, 0.5 in Donganme, and 0.4 in Hwanggeumchal. Meanwhile, there was no distinct connection between damaging results and yields of maizes and sorghums by O. furnacalis larvae in a paddy-upland rotation field. These results from this study can be applicable for the establishment of a management strategy to control Oriental corn borer in paddy-upland rotation fields for maize and sorghum.

• Sijohaknonchong
• /
• v.44
• /
• pp.197-236
• /
• 2016

The aim of this study is to discover the distinctive aspects of Sijo in the 17th Century through five old music scores, "梁琴新譜Yangqeumsinbo", "白雲庵琴譜 baekwoonamgeumbo", "增補古琴譜jeungbogogeumbo", "延世大學校所藏琴譜geumbo in Yonsei University", "琴譜古geumbogo", which were compiled in this time period. First, four Sijo works are found from the "梁琴新譜Yangqeumsinbo" and one of them is noteworthy because it was sung as 中大葉Jungdaeyeop, 初中大葉 Chojungdaeyeop, 二中大葉Yijungdaeyeop and showed signs to fit the Sijo format type since the 17th century. In "白雲庵琴譜baekwoonamgeumbo", there are three Sijo works (one has recorded music scores and two don't) and one of them is discovered with last phrase being omitted. In "延世大學校所藏琴譜geumbo in Yonsei University", there are 9 Sijo works performed with 中大葉Jungdaeyeop. In "增補古琴譜 jeungbogogeumbo", there are three works performed with 數大葉Sakdaeyeop and one of them is noteworthy as a clue about the relations between Sijo and Goryeosokyo because it is a modified work which adapted the Goryeosokyo "Gasiri" according to the Sijo format. In 琴譜古geumbogo, there are three works with high possibility that repertoire with 中大葉Jungdaeyeop were already set up at this time. Based on these five music scores, it can be mentioned that a lot of Geumbos were compiled in 17th century, not for the purpose of enlightening discourse at the national level but for referencing for music lovers by themselves to memorize songs individually. It is also discovered that Sijo was performed with only 平調pyeong-jo out of 羽調woo-jo, 羽調界面調woojokyemyen-jo, 平調pyeong-jo, 平調界面調pyeongjokyemyun-jo in early 17th century, but it was performed with other three and 數大葉Sakdaeyeop as well after the mid-17th century. On the other hand, despite the change in the musical tunes, lyrics do not show a significant change at this time because it is estimated repertoire with specific piece of music was already formed in 17th Century. However, performing itself would give a certain impact on change and loss of lyrics because it tends to focus on communication and emotional connection between singers and audience. Clarifying characteristics in Sijo from old music scores is meaningful in that Sijo can be understood better not only as written poetry but also as oral poetry and overcome bias of previous researches which have been proceeded mainly on Sijo lyrics collection(歌集).

• Journal of agriculture & life science
• /
• v.45 no.2
• /
• pp.125-133
• /
• 2011

This study was conducted on greenhouses whose side heights had been raised after the columns of 1-2W basic type greenhouses had been cut and welding with the same-sized pipes. When the wind load or snow load affects restructured pipe greenhouse like this, those parts will be structurally unsafe. To examine this, the bending strength of welded columns were measured through four stages and compared with the pipes in their original condition. Results are as follows. In the case of a bending test on welded joints about steel pipes used for greenhouses, satisfactory results couldn't be drawn because sections of both ends and the loading parts couldn't endure loads and sank regardless of loading methods. Partial problems could be solved by inserting inside pipe(steel bar) at the sections and the loading parts, but it was necessary to devise more satisfactory bending test methods. The strength of welded joints wasn't much different compared with original conditions and demonstrated only slight differences according to the sample production conditions. However, significant incompleteness in the welding process was expected to cause a decisive loss in strength. On the assumption that there were no problems in the welding process or with regard to the inclination of sub materials for columns after connection, it was deemed reasonable to assume that the strength of welded pipes was about 84~90% of the strength of the pipes in their original condition. Considering mid- and long-term strength decline following the onset of rust at joints or welding sections, structural changes in the main sub materials that are used for greenhouses at farmhouses have to be avoided to ensure structural safety, unless these changes are inevitable.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.41 no.2
• /
• pp.1-10
• /
• 2023

This study aims to explore the significance of historic changes and cultural characteristics of landscape architecture in Korean Seowon. Seowon refers to educational private institutes that also served as Confucian shrines and were prevalent during the mid-to-late Joseon dynasty. Seowon comprised three distinct functional spaces: a shrine, a school, and a garden. The concept of Seowon's garden extended beyond designed landscapes to include the surrounding natural environment. The importance of landscape architecture in Seowon is rooted in its connection to the educational philosophy of these institutes. During the Joseon dynasty, scholars revered nature as a manifestation of Confucian ideals, and they believed that close engagement with nature was integral to self-discipline and learning. This research investigated fifteen relatively well-preserved garden in South Korea and conducted a comprehensive analysis of their gardens. The analysis revealed two key findings. Firstly, gardens in Seowon were actively designed and constructed during the early phase of Seowon culture but gradually diminished after the 17th century. This can be attributed to the shift in Seowon's purpose, with a greater emphasis on its religious function over education. Consequently, the significance and presence of landscape architecture in Seowon, which was closely related with its Confucianist education, declined. Secondly, the study explored the historical backgrounds of each Seowon's landscape architecture and found that many of them were designed or influenced by individuals who were later memorialized and deified in the Seowon's shrines. The landscape architecture created by these predecessors was carefully preserved by the faculties and students as a form of respect. Therefore, landscape architecture in Korean Seowon not only conveys the institutional purpose as an educational hub for the local society but also reflects the institute's strong relationship with the figures they worship as shrines.

• Korean Journal of Culture and Social Issue
• /
• v.23 no.2
• /
• pp.183-214
• /
• 2017

The purpose of this study was to examine the psychological characteristics of affecting never married men and women through analyzing the content of in-depth interviews about the idea of marriage and the reason for never married choice. For achieving this purpose, the in-depth interview was conducted with 9 men and women aged mid-20s to late 30s who said to choose never married life for a long time, and then the content of interview was analyzed using consensual qualitative research. As a result of analyzing the content of in-depth interview, it was derived into 2 areas, 10 sub-areas, and 25 categories. The results of the study were as follows. Firstly, it was found that research participants negatively recognized the marriage and had unrealistic expectation rather than no expectation for marriage. Secondly, most of the research participants felt negative feelings about their parents' patriarchal role, and they did not want to live like their parents. They also reported that they did not see their marriage separated from their parents. Thirdly, most of the research participants felt difficulty in forming relationships with intimate person, and it became more difficult to have expectations about spouses and marriage due to repeated relationship conflict patterns. Fourthly, the research participants showed psychological aspect of experiential avoidance and seeking for individuality in terms of never married choice. Most of the research participants predicted the failure of married life, and reported that they were trying to prevent uncomfortable feelings and sufferings by choosing never married life. Also they reported that individuality considered more important than connection with others(togetherness) and individual value considered more important than collective value. Participants in this study showed negative evaluation or had negative influences on the marriage life of parents and acquaintances. This is more likely to be a passive factor in never married choice, so future research should examine the characteristics of active factors in never married choice.

• Proceedings of the KOR-BRONCHOESO Conference
• /
• 1982.05a
• /
• pp.17.2-19
• /
• 1982

The sinus tympani is subject to great variability in the size, shape and posterior extent. A heavy compact bony zone, especially in the posterior portion and the narrow space between the facial nerve and posterior semicircular canal are the limitation of surgical approach. The facial recess should be opened, creating a wide connection between the mesotympanum and mastoid in the Intact canal wall tympanoplasty with mastoidectomy. The surgically created limits of the facial recess are the facial nerve medially, the chorda tympani laterally and the bone adjacent to the incus superiorly. Using adult Korean's thirty-five temporal bones, the authors measured the osteologic reslationship in the posterior tympanum, especially sinus tympani and facial recess. The result was as followed. 1. The average distance from the anterior end of the pyramidal eminence. 1) to the edge of the sinus tympani directly posterior was 2.54(1.05-5.40)mm. 2) to the maximum posterior extent was 3.22(1.25-7.45)mm. 3) to the maximum cephaled extent was 0.67 (0.40-1.75)mm. 2. The boundary of the sinus tympani was 82.9% from the lower margin oval window to the upper margin round window niche. 3. The deepest part of the sinus tympani was 62.9% in the mid portion, between the ponticulus and subiculum. 4. The oblique dimension from the fossa incudis above to the hypotympanum below was 8.13(7.90-9.55)mm. 5. The transverse dimensions midway between the oval window above and round window below was 3.00(2.85-3.45)mm. 6. The transverse dimension at the level of the fossa incudis was 1.81(1.40-2.15)mm. 7. The facial nerve dehiscence was 14.3%. 8. Anterior-posterior diameter of the footplate was 2.98(2.85-3.05) mm. 9. The average distance from the footplate. 1) to the cochleariform process was 1.42(1.35-1.55) mm. 2) to the round window niche was 1.85(1.45-2.10) mm.