• Title/Summary/Keyword: 자연학

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A Study on Control Possibility of Ambrosia trifida L., an Invasive Alien Plant by the Feeding of Ophraella communa LeSage (돼지풀잎벌레의 섭식에 의한 생태계교란 식물인 단풍잎돼지풀의 제어 가능성 연구)

  • SooIn Lee;JaeHoon Park;EuiJoo Kim;JiWon Park;JungMin Lee;YoonSeo Kim;SeHee Kim;YeoBin Park;EungPill Lee
    • Journal of Wetlands Research
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    • v.25 no.3
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    • pp.184-195
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    • 2023
  • To develop an effective management plan for Ambrosia trifida L., an invasive alien plant in Korea, we assessed the potential of Ophraella communa LeSage as a biological control agent. This involved investigating the host specificity of the herbivore Ophraella communa LeSage, its annual travel distance, and the impact of this insect on the fitness of Ambrosia trifida L. We confirmed the host plant preference of Ophraella communa LeSage. The travel distance of this insect was determined by monitoring its appearance in selected Ambrosia trifida L. communities without these insects at distances of 10, 20, 30, and 100 meters, based on the locations where the presence of Ophraella communa LeSage was observed. The growth, reproductive, and physiological responses of Ambrosia trifida L. were measured according to feeding by Ophraella communa LeSage. As a result, Ophraella communa LeSage fed on only three taxa and moved short distances within a radius of 30 m per year from the host. The feeding behavior of the herbivore had a negative impact on the growth, reproductive, and physiological responses of Ambrosia trifida L. And the plant's growth and reproduction improved with increasing distance from the herbivore. Furthermore, the introduction of herbivores was able to control over 90% of Ambrosia trifida L. when the coverage of the Ambrosia trifida L. group was below 50%. However, the effectiveness of the removal decreased when the coverage exceeded 90%. These results are likely to be utilized by Ophraella communa LeSage as an ecological control agent. It is advantageous to introduce them in spring (May) when the coverage is low to maximize the effectiveness of control.

Increased Water Resistance and Adhesion Force to Skin through the Hybrid of Fatty Acid Ester and Titanium Dioxide (지방산 에스테르와 티타늄다이옥사이드의 복합화를 통한 내수성과 피부 밀착력 개선)

  • Ji Yeon Hong;Chi Je Park;Yong Woo Kim;Sang Keun Han;Sung Bong Kye;Ho Sik Roh;Soo Nam Park
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.49 no.3
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    • pp.247-258
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    • 2023
  • This study aims to investigate the enhancement of water resistance and improvement in adhesion to the skin by combining dextrin palmitate and isopropyl titanium triisostearate coating materials with titanium dioxide. Due to the recent increase in consumers who enjoy outdoor activities, the demand for sunscreen with excellent water resistance is increasing. Prior research was conducted with O/W, Pickering, and W/O/W multiple formulations, but there was a limit to water resistance. The purpose of this study is to develop a complex inorganic powder that can improve water resistance and increase adhesion to the skin to solve this problem. First, we combined dextrin palmitate and isopropyl titanium triisostearate coating materials to form a composite with titanium dioxide. The coating of the inorganic powder was confirmed using FE-SEM and FT-IR analysis. The composite exhibited significantly higher in vitro water resistance compared to other formulations. The hydrophobicity of the coated inorganic powder was compared by measuring the contact angles. When the coated inorganic powder was applied to the W/O sunscreen formulation and the non-coated inorganic powder was applied to the W/O sunscreen formulation as a control, the SPF of the sunscreen containing the coated inorganic powder was higher. These results were the same when observed with a UV camera. Finally the adhesion of the coated inorganic powder to the skin was assessed by applying it to a foundation product. In vivo study, it was observed that the product formulated with the coated powder exhibited less smudging compared to the foundation product formulated with the non-coated powder. The developed inorganic powder in this study demonstrated excellent adhesion to the skin, providing a superior sensory experience, as well as enhanced hydrophobicity and remarkable water resistance effects. In the future, the result of this study is expected to help develop various sunscreen products to improve water resistance.

Ecological Renewal Plan of Urban Parks for the Revitalization of Urban Green Axis in Gangdong-Gu (강동구 도시 녹지축 기능 활성화를 위한 도시공원의 생태적 리뉴얼 방안 연구)

  • Park, Jeong-Ah;Han, Bong-Ho;Kwak, Jeong-In
    • Journal of the Korean Institute of Landscape Architecture
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    • v.51 no.2
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    • pp.12-27
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    • 2023
  • In this study, among the construction-type parks in Gangdong-gu, targeting parks with high environmental and ecological value located on the urban green axis, a plan was prepared for the ecological renewal of urban parks, and a design that applied to them was proposed. The renewal target site was selected by analyzing the general condition of Gangdong-gu and urban parks, the land use and green area ratio, park green area, and the green axis of Gangdong-gu. Gangdong-gu has 54 parks, including 2 neighborhood parks and 52 children's parks. In the first stage of the current status review, 17 parks were extracted through locational value analysis, such as location and adjacency to the natural axis and green axis. In the second stage, eight parks were selected among the first-stage extraction parks based on the ratio of green spaces and open spaces within each park service area. In the third stage, two of the second stage extraction parks were selected based on whether the legal standard of the park area was met, and in the fourth stage, one of the third stage extraction parks was selected through an aging survey of the park. As for the urban ecological status of the renewal target site, the status of land use in the aspect of entropy reduction, the status of soil cover in the aspect of water circulation, and the status of planting structure in the aspect of biodiversity were investigated. As for the status of the three renewal sites, the green area was insufficient at 18.3-45.3%, and the facility area was 54.7%-81.7%, which was judged to have low urban temperature reduction effects. The impervious pavement area accounted for 34.5% to 48.9% of the park area, accounting for most of the facility area, and it was judged that the water circulation function was insufficient. The planting structure consisted of a single layer and a double layer structure, and although the tree layer was good, the lower vegetation was poor, and there was no planting site of edible plants or large hardwood trees, so the biodiversity was low. After the ecological renewal design of Seonrin Children's Park, Dangmal Children's Park, and Saemmul Children's Park, which were selected as the renewal targets in this study, the ecological area ratio of each park increased by 1.4 to 3 times than before the renewal. If the urban parks located on the urban green axis are examined from the perspective of the urban ecosystem and renewed ecologically, it is judged that the expected effect will be high in reducing entropy, improving water circulation, and laying the foundation for biodiversity in terms of the urban ecosystem.

A Study on Mutual Aid and Mutual Contention of the Ten Celestial Stems and Twelve Earthly Branches (천간과 지지의 상조(相助)와 상극(相剋)에 관한 연구)

  • Woo Yeon-hwa;Kim Man-tae
    • Journal of the Daesoon Academy of Sciences
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    • v.42
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    • pp.109-141
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    • 2022
  • As many perhaps already know, in East Asian thought there are two aspects of all things such as light and darkness coexist and are called Yin-Yang (陰陽). The initial concept of Yin-Yang was just a simple expression meant to depict natural phenomena, but it gradually became the central concept in explanations of creation and the changes that undergo all things in the universe. The study of the ordering principle of nature that was known as Myeongli (命理) also examined the interrelation between the sky and the earth and divided the two into Ten Celestial Stems (天干 cheongan) and the Twelve Earth Branches (地支 jiji) based on Yin-Yang theory. This thesis analyzed contents of the relationship between Ten Celestial Stems and the Twelve Earth Branches in terms of the patterns of Mutual Aid (相助 sangjo) and Mutual Contention (相剋 sanggeuk) through a literature review and exploration of their common features and differences. Different categorized phenomena under the pattern of Mutual Aid include Tonggeun (通根 root downward) and Tugan (透干 appearance of the upward). Tonggeun means that signs in the Celestial Stems took root in their counterparts of the Earthly Branches. In the Celestial Stems, there is also Tonggeuncheo (通根處 a place to root downward) which in relation to the Earthly Branches show that the same five phases become Samhap (三合 combined three ways to gain power) and Banghap (方合 gathering in the same season). The methods of seeing Tonggeunryeok (通根力 power of a downward root) are as follows: First, it is seen by the places where Tonggeun takes hold. Ilgan (日干 the Celestial Stem of a birthday) is ordered as month (月 wol) > day (日 il) > hour (時 shi) > year (年 nyeon), and other Celestial Stems appear ordered as month > sitting > close place. Second, it can be seen by the characteristics of Earthly Branches that Tonggeun has taken hold. The Earthly Branches are ordered as Rokwangji (祿旺支 vigorous land) and Jangsaengji (長生支 newborn land) > Yeogi (餘氣 remaining energy) > Myogo (墓庫 storage and burial grounds). Tugan is the concept that the main agent was changed to Tonggeun, which means that the spirit of the Earthly Branches is manifested in the Celestial Stems. And the five phases hidden in the Earthly Branches will be able to play their roles as they are revealed. There are also the phenomena of Gaedu (蓋頭 the heavenly destroying the earthly) and Jeolgak (截脚 the earthly destroying the heavenly) which are concepts that convey that the Heavenly Stems and Earthly Branches can mutually destroy one another. There are different opinions on Gaedu because some adopt viewpoints of just focusing on the Celestial Stems and considering it only in terms the Celestial Stems destroying the Earthly Branches. But, the vast majority of scholars think that the Celestial Stems weakens the role of the roots by destroying the Earthly Branches. Jeolgak, the reverse concept of Gaedu, weakens the spirit of the Celestial Stems as the Earthly Branches destroy them, and this is associated with the strong possibility that one is fated to experience disharmony.

Manufacture and Characteristics of Peel-off Pack for Natural Cosmetics Using Pullulan and Polysaccharides (Pullulan과 Polysaccharides를 이용한 천연화장품용 필 오프 팩의 제조 및 특성)

  • Jun Soo Kwak;So Young Jung;So Min Lee;Seok-Ju Lee;Sofia Brito;Byungsun Cha;Hyojin Heo;Lei Lei;Sang Hun Lee;Ha-Hyeon Jo;You-Yeon Chun;Ye Ji Kim;Hyung Mook Kim;Mi-Gi Lee;Byeong-Mun Kwak;Bum-Ho Bin
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.49 no.1
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    • pp.67-74
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    • 2023
  • In this study, for a natural cosmetics market, we sought to explore alternatives that can replace polyvinyl alcohol (PVA) of peel-off packs. A peel-off type pack was prepared by combining pullulan, a water-soluble polysaccharide, and other polysaccharides (sodium hyaluronate, cellulose gum, hydroxyethyl cellulose, sodium alginate, corn starch), and the pH, viscosity, and stability against temperature of each peel-off type pack were confirmed. The thickness and tensile strength of the manufactured film were measured for comparison with the PVA peel-off type pack, and applicability, drying speed, and removal degree were measured. Among them, the pullulan-sodium hyaluronate peel-off type pack showed excellent film formation ability to replace the peel-off type pack containing PVA with 5.12% thin film thickness and 4.23% high film tensile strength. When applied to actual skin, the degree of spread of the pack, the usability that can be uniformly applied, and the formation and removal strength of the film when removed after drying were also similar to the peel-off type pack containing PVA. Therefore, it was confirmed that the film formed of pullulan-sodium hyaluronate showed enough physical properties to replace the PVA of the peel-off type pack as a natural peel-off type pack.

Development of disaster severity classification model using machine learning technique (머신러닝 기법을 이용한 재해강도 분류모형 개발)

  • Lee, Seungmin;Baek, Seonuk;Lee, Junhak;Kim, Kyungtak;Kim, Soojun;Kim, Hung Soo
    • Journal of Korea Water Resources Association
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    • v.56 no.4
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    • pp.261-272
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    • 2023
  • In recent years, natural disasters such as heavy rainfall and typhoons have occurred more frequently, and their severity has increased due to climate change. The Korea Meteorological Administration (KMA) currently uses the same criteria for all regions in Korea for watch and warning based on the maximum cumulative rainfall with durations of 3-hour and 12-hour to reduce damage. However, KMA's criteria do not consider the regional characteristics of damages caused by heavy rainfall and typhoon events. In this regard, it is necessary to develop new criteria considering regional characteristics of damage and cumulative rainfalls in durations, establishing four stages: blue, yellow, orange, and red. A classification model, called DSCM (Disaster Severity Classification Model), for the four-stage disaster severity was developed using four machine learning models (Decision Tree, Support Vector Machine, Random Forest, and XGBoost). This study applied DSCM to local governments of Seoul, Incheon, and Gyeonggi Province province. To develop DSCM, we used data on rainfall, cumulative rainfall, maximum rainfalls for durations of 3-hour and 12-hour, and antecedent rainfall as independent variables, and a 4-class damage scale for heavy rain damage and typhoon damage for each local government as dependent variables. As a result, the Decision Tree model had the highest accuracy with an F1-Score of 0.56. We believe that this developed DSCM can help identify disaster risk at each stage and contribute to reducing damage through efficient disaster management for local governments based on specific events.

Current status of cherry trees (Prunus subg. Cerasus) planted in Korea: A case study of Bundang Central Park and adjacent area (국내 벚나무류(Prunus subg. Cerasus) 식재 현황: 분당중앙공원 일대 사례연구)

  • HAN, Byungwoo;JUNG, Jongduk;NA, Hye Ryun;KANG, Kyoungsuk;CHANG, Hany;KIM, Seryoung;KIM, Youme;KWON, Heejeong;HYUN, Jin-Oh
    • Korean Journal of Plant Taxonomy
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    • v.52 no.1
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    • pp.54-63
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    • 2022
  • Prunus subg. Cerasus is the most planted street and landscaping tree in South Korea, but it is difficult to identify species according to their macro-morphologies, leading to problems when attempting properly to manage species quantities. The purpose of this study is to understand the current status of plant types and species compositions in Bundang Central Park in Bundang-gu of Seongnam City and to discuss the necessity of the management of landscaping tree planting. In April of 2021, during the cherry blossom season, a total of 5,866 planted cherry trees were investigated within an area of 6 km2 of Bundang-gu in Seongnam City. As a result, 5,744 trees were sorted into eleven taxa, but the remaining 122 trees were not determined due to their complex morphologies. Prunus ×yedoensis Matsum. accounted for the highest proportion (52.1%), followed by P. serrulata Lindl. var. pubescens Nakai and P. jamasakura Siebold ex Koidz. P. ×nudiflora (Koehne) Koidz., a plant native to Jejudo Island, was not found in this survey. In order to help identify cherry trees based on micro-morphologies, an identification key was presented for the eleven taxa planted as major landscaping trees. It is known that cherry trees frequently form interspecific hybrids in nature. In order to prevent a loss of the genetic originality of native species due to hybridization and gene introgression from foreign cherry trees, it is necessary to manage planting species near the habitats of native taxa and track their origins.

The Optimal Surgical Approach and Complications in Resecting Osteochondroma around the Lesser Trochanter (소전자부 주위의 골연골종 절제 시 적절한 외과적 접근법과 합병증)

  • Jeon, Dae-Geun;Cho, Wan Hyeong;Song, Won Seok;Kong, Chang-Bae;Lee, Seung Yong;Kim, Do Yup
    • Journal of the Korean Orthopaedic Association
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    • v.52 no.1
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    • pp.33-39
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    • 2017
  • Purpose: Surgical risks associated with the resection of osteochondroma around the proximal tibia and fibula, as well as the proximal humerus have been well established; however, the clinical presentation and optimal surgical approach for osteochondroma around the lesser trochanter have not been fully addressed. Materials and Methods: Thirteen patients with osteochondroma around the lesser trochanter underwent resection. We described the chief complaint, duration of symptom, location of the tumor, mass protrusion pattern on axial computed tomography image, tumor volume, surgical approach, iliopsoas tendon integrity after resection, and complication according to the each surgical approach. Results: Pain on walking or exercise was the chief complaint in 7 patients, and numbness and radiating pain in 6 patients. The average duration of symptom was 19 months (2-72 months). The surgical approach for 5 tumors that protruded postero-laterally was postero-lateral (n=3), anterior (n=1), and medial (n=1). All 4 patients with antero-medially protruding tumor underwent the anterior approach. Two patients with both antero-medially and postero-laterally protruding tumor received the medial and anterior approach, respectively. Two patients who underwent medial approach for postero-laterally protruded tumor showed extensive cortical defect after resection. One patient who received the anterior approach to resect a large postero-laterally protruded tumor developed complete sciatic nerve palsy, which was recovered 6 months after re-exploration. Conclusion: For large osteochondromas with posterior protrusion, we should not underestimate the probability of sciatic nerve compression. When regarding the optimal surgical approach, the medial one is best suitable for small tumors, while the anterior approach is good for antero-medial or femur neck tumor. For postero-laterally protruded large tumors, posterior approach may minimize the risk of sciatic nerve palsy.

Study on VOCs Emission Characteristic of Taxidermied Mounting Techniques (박제표본 제작방법에 따른 휘발성유기화합물 방출 특성 연구)

  • OH Jungwoo;CHUNG Yongjae
    • Korean Journal of Heritage: History & Science
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    • v.56 no.2
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    • pp.136-146
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    • 2023
  • Biological materials, such as stuffed specimens, can release various acids or volatiles. There has been no research carried out on the emission characteristics of organic compounds generated from the preservatives used in taxidermy specimens or associated manufacturing materials and methods. Therefore, in order to identify the organic compounds generated from taxidermy specimens, a degradation experiment was conducted on specimens for each material and for storage specimens. To produce Ogye chicken specimens, naphthalene and borax were used as preservatives, and planer sawdust, newspaper, and polystyrene foam were used as the core body materials. The deterioration experiment was conducted for 2 weeks in a high-temperature environment(50℃) and a high-humidity environment (95%), with an Ogye chicken specimen (year 2015) kept in an animal storage facility. Results indicated that the concentration of organic compounds generated by the specimen in the high-temperature environment tended to be greater than that in the high-humidity environment. The preservatives benzene, toluene, xylene, and p-dichlorobenzene were detected in the specimens using naphthalene, confirming that naphthalene is a major organic compound release factor, and the specimens that used sawdust, newspaper, and polystyrene foam also exhibited organic compounds. This appears to have been due to degradation of the material. In addition, ammonia was detected in the specimens for each material due to decay. In particular, the specimens using borax at high temperature were subject to approximately 9 times higher rates of ammonia-related deterioration than the specimens using naphthalene. These results can be considered to result from the prevention of biological damage through insecticidal effects by accelerating the sublimation of naphthalene in a high-temperature environment. Naphthalene is a potentially carcinogenic substance, and when used as a preservative, proper use management is required. Taxidermy specimens can release various organic compounds depending on the manufacturing techniques used, so a systematic preservation management plan is required that depends on conditions such as the applicable manufacturing materials and preservatives.

Development of 1ST-Model for 1 hour-heavy rain damage scale prediction based on AI models (1시간 호우피해 규모 예측을 위한 AI 기반의 1ST-모형 개발)

  • Lee, Joonhak;Lee, Haneul;Kang, Narae;Hwang, Seokhwan;Kim, Hung Soo;Kim, Soojun
    • Journal of Korea Water Resources Association
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    • v.56 no.5
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    • pp.311-323
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    • 2023
  • In order to reduce disaster damage by localized heavy rains, floods, and urban inundation, it is important to know in advance whether natural disasters occur. Currently, heavy rain watch and heavy rain warning by the criteria of the Korea Meteorological Administration are being issued in Korea. However, since this one criterion is applied to the whole country, we can not clearly recognize heavy rain damage for a specific region in advance. Therefore, in this paper, we tried to reset the current criteria for a special weather report which considers the regional characteristics and to predict the damage caused by rainfall after 1 hour. The study area was selected as Gyeonggi-province, where has more frequent heavy rain damage than other regions. Then, the rainfall inducing disaster or hazard-triggering rainfall was set by utilizing hourly rainfall and heavy rain damage data, considering the local characteristics. The heavy rain damage prediction model was developed by a decision tree model and a random forest model, which are machine learning technique and by rainfall inducing disaster and rainfall data. In addition, long short-term memory and deep neural network models were used for predicting rainfall after 1 hour. The predicted rainfall by a developed prediction model was applied to the trained classification model and we predicted whether the rain damage after 1 hour will be occurred or not and we called this as 1ST-Model. The 1ST-Model can be used for preventing and preparing heavy rain disaster and it is judged to be of great contribution in reducing damage caused by heavy rain.