• Title/Summary/Keyword: 두께 손실

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Application of Environmental Friendly Bio-adsorbent based on a Plant Root for Copper Recovery Compared to the Synthetic Resin (구리 회수를 위한 식물뿌리 기반 친환경 바이오 흡착제의 적용 - 합성수지와의 비교)

  • Bawkar, Shilpa K.;Jha, Manis K.;Choubey, Pankaj K.;Parween, Rukshana;Panda, Rekha;Singh, Pramod K.;Lee, Jae-chun
    • Resources Recycling
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    • v.31 no.4
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    • pp.56-65
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    • 2022
  • Copper is one of the non-ferrous metals used in the electrical/electronic manufacturing industries due to its superior properties particularly the high conductivity and less resistivity. The effluent generated from the surface finishing process of these industries contains higher copper content which gets discharged in to water bodies directly or indirectly. This causes severe environmental pollution and also results in loss of an important valuable metal. To overcome this issue, continuous R & D activities are going on across the globe in adsorption area with the purpose of finding an efficient, low cost and ecofriendly adsorbent. In view of the above, present investigation was made to compare the performance of a plant root (Datura root powder) as a bio-adsorbent to that of the synthetic one (Tulsion T-42) for copper adsorption from such effluent. Experiments were carried out in batch studies to optimize parameters such as adsorbent dose, contact time, pH, feed concentration, etc. Results of the batch experiments indicate that 0.2 g of Datura root powder and 0.1 g of Tulsion T-42 showed 95% copper adsorption from an initial feed/solution of 100 ppm Cu at pH 4 in contact time of 15 and 30 min, respectively. Adsorption data for both the adsorbents were fitted well to the Freundlich isotherm. Experimental results were also validated with the kinetic model, which showed that the adsorption of copper followed pseudo-second order rate expression for the both adsorbents. Overall result demonstrates that the bio-adsorbent tested has a potential applicability for metal recovery from the waste solutions/effluents of metal finishing units. In view of the requirements of commercial viability and minimal environmental damage there from, Datura root powder being an effective material for metal uptake, may prove to be a feasible adsorbent for copper recovery after the necessary scale-up studies.

Oral administration of H. syriacus L. flower ameliorates photoaging and dryness in UVB-irradiated skin (무궁화 꽃 추출물 경구투여에 의한 피부 광노화 및 건조증 개선에 관한 효과)

  • Yang, Jung-Eun;Seo, Seul A;Kang, Min Cheol;Yoon, Da Hye;Im, Tae Joon;Hwang, Eunson;Won, Kyung Hwa;Lee, Teak Hwan;Kim, Sun Yeou
    • Korean Journal of Food Science and Technology
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    • v.53 no.4
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    • pp.399-407
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    • 2021
  • Wrinkle formation and dryness are the most well-known symptoms of skin aging. This study investigated skin anti-aging and moisturizing effects of Mugunghwa (Hibiscus syriacus L.), the national flower of Korea. The effect of H. syriacus L. flower extract was examined in skin cells originating from humans in vitro and in hairless mice exposed to UVB in vivo. The in vivo study results showed that skin hydration-related factors such as involucrin, filaggrin, HAS1, HYAL1, and matrix metalloproteinase-I (a primary skin photoaging factor) were regulated by H. syriacus L. Additionally, epidermal thickness and collagen disruption, which resulted in wrinkle formation and skin dryness, were ameliorated by oral administration of H. syriacus L. These results indicate that H. syriacus L. flowers can play important roles in preventing aging and promoting skin moisturizing.

A preliminary assessment of high-spatial-resolution satellite rainfall estimation from SAR Sentinel-1 over the central region of South Korea (한반도 중부지역에서의 SAR Sentinel-1 위성강우량 추정에 관한 예비평가)

  • Nguyen, Hoang Hai;Jung, Woosung;Lee, Dalgeun;Shin, Daeyun
    • Journal of Korea Water Resources Association
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    • v.55 no.6
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    • pp.393-404
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    • 2022
  • Reliable terrestrial rainfall observations from satellites at finer spatial resolution are essential for urban hydrological and microscale agricultural demands. Although various traditional "top-down" approach-based satellite rainfall products were widely used, they are limited in spatial resolution. This study aims to assess the potential of a novel "bottom-up" approach for rainfall estimation, the parameterized SM2RAIN model, applied to the C-band SAR Sentinel-1 satellite data (SM2RAIN-S1), to generate high-spatial-resolution terrestrial rainfall estimates (0.01° grid/6-day) over Central South Korea. Its performance was evaluated for both spatial and temporal variability using the respective rainfall data from a conventional reanalysis product and rain gauge network for a 1-year period over two different sub-regions in Central South Korea-the mixed forest-dominated, middle sub-region and cropland-dominated, west coast sub-region. Evaluation results indicated that the SM2RAIN-S1 product can capture general rainfall patterns in Central South Korea, and hold potential for high-spatial-resolution rainfall measurement over the local scale with different land covers, while less biased rainfall estimates against rain gauge observations were provided. Moreover, the SM2RAIN-S1 rainfall product was better in mixed forests considering the Pearson's correlation coefficient (R = 0.69), implying the suitability of 6-day SM2RAIN-S1 data in capturing the temporal dynamics of soil moisture and rainfall in mixed forests. However, in terms of RMSE and Bias, better performance was obtained with the SM2RAIN-S1 rainfall product over croplands rather than mixed forests, indicating that larger errors induced by high evapotranspiration losses (especially in mixed forests) need to be included in further improvement of the SM2RAIN.

High-Risk Area for Human Infection with Avian Influenza Based on Novel Risk Assessment Matrix (위험 매트릭스(Risk Matrix)를 활용한 조류인플루엔자 인체감염증 위험지역 평가)

  • Sung-dae Park;Dae-sung Yoo
    • Korean Journal of Poultry Science
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    • v.50 no.1
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    • pp.41-50
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    • 2023
  • Over the last decade, avian influenza (AI) has been considered an emerging disease that would become the next pandemic, particularly in countries like South Korea, with continuous animal outbreaks. In this situation, risk assessment is highly needed to prevent and prepare for human infection with AI. Thus, we developed the risk assessment matrix for a high-risk area of human infection with AI in South Korea based on the notion that risk is the multiplication of hazards with vulnerability. This matrix consisted of highly pathogenic avian influenza (HPAI) in poultry farms and the number of poultry-associated production facilities assumed as hazards of avian influenza and vulnerability, respectively. The average number of HPAI in poultry farms at the 229-municipal level as the hazard axis of the matrix was predicted using a negative binomial regression with nationwide outbreaks data from 2003 to 2018. The two components of the matrix were classified into five groups using the K-means clustering algorithm and multiplied, consequently producing the area-specific risk level of human infection. As a result, Naju-si, Jeongeup-si, and Namwon-si were categorized as high-risk areas for human infection with AI. These findings would contribute to designing the policies for human infection to minimize socio-economic damages.

Visible and SWIR Satellite Image Fusion Using Multi-Resolution Transform Method Based on Haze-Guided Weight Map (Haze-Guided Weight Map 기반 다중해상도 변환 기법을 활용한 가시광 및 SWIR 위성영상 융합)

  • Taehong Kwak;Yongil Kim
    • Korean Journal of Remote Sensing
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    • v.39 no.3
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    • pp.283-295
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    • 2023
  • With the development of sensor and satellite technology, numerous high-resolution and multi-spectral satellite images have been available. Due to their wavelength-dependent reflection, transmission, and scattering characteristics, multi-spectral satellite images can provide complementary information for earth observation. In particular, the short-wave infrared (SWIR) band can penetrate certain types of atmospheric aerosols from the benefit of the reduced Rayleigh scattering effect, which allows for a clearer view and more detailed information to be captured from hazed surfaces compared to the visible band. In this study, we proposed a multi-resolution transform-based image fusion method to combine visible and SWIR satellite images. The purpose of the fusion method is to generate a single integrated image that incorporates complementary information such as detailed background information from the visible band and land cover information in the haze region from the SWIR band. For this purpose, this study applied the Laplacian pyramid-based multi-resolution transform method, which is a representative image decomposition approach for image fusion. Additionally, we modified the multiresolution fusion method by combining a haze-guided weight map based on the prior knowledge that SWIR bands contain more information in pixels from the haze region. The proposed method was validated using very high-resolution satellite images from Worldview-3, containing multi-spectral visible and SWIR bands. The experimental data including hazed areas with limited visibility caused by smoke from wildfires was utilized to validate the penetration properties of the proposed fusion method. Both quantitative and visual evaluations were conducted using image quality assessment indices. The results showed that the bright features from the SWIR bands in the hazed areas were successfully fused into the integrated feature maps without any loss of detailed information from the visible bands.

Contaminant Mechanism and Management of Tracksite of Pterosaurs, Birds, and Dinosaurs in Chungmugong-dong, Jinju, Korea (천연기념물 진주 충무공동 익룡·새·공룡발자국 화석산지의 오염물 형성 메커니즘과 관리방안)

  • Myoungju Choie;Sangho Won;Tea Jong Lee;Seong-Joo Lee;Dal-Yong Kong;Myeong Seong Lee
    • Economic and Environmental Geology
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    • v.56 no.6
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    • pp.715-728
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    • 2023
  • Tracksite of pterosaurs, birds, and dinosaurs in Chungmugong-dong in Jinju was designated as a natural monument in 2011 and is known as the world's largest in terms of the number and density of pterosaur footprints. This site has been managed by installing protection buildings to conserve in 2018. About 17% of the footprints of pterosaur, theropod, and ornithopod in this site under management in the 2nd protection building are of great academic value, but observation of footprints has difficulties due to continuous physical and chemical damage. In particular, the accumulation of milk-white contaminants is formed by the gypsum and air pollutant complex. Gypsum remains evaporated with a plate or columnar shape in the process of water circulation around the 2nd protection building, and the dust is from through the inflow of the gallery windows. The aqueous solution of gypsum, consisting of calcium from the lower bed and sulfur from grass growth, is catchmented into the groundwater from the area behind the protection building. Pollen and a few minerals other constituents of contaminants, go through the gallery window, which makes it difficult to expel dust. To conserve the fossil-bearing beds from two contaminants of different origins, controlling the water and atmospheric circulation of the 2nd protection building and removing the contaminants continuously is necessary. When cleaning contaminants, the steam cleaning method is sufficiently effective for powder-shaped milk-white contaminants. The fossil-bearing bed consists of dark gray shale with high laser absorption power; the laser cleaning method accompanies physical loss to fossils and sedimentary structures; therefore, avoiding it as much as possible is desirable.

Agricultural and Sprouts Characteristics of Mung Bean (Vigna radiata L.) Cultivated in Southern Areas According to Sowing Dates (파종시기에 따른 남부지역 재배 녹두의 생육 및 나물특성 변화)

  • Ji Ho Chu;Byeong Won Lee;Yeong Kwang Ju;Ju Seong Im;Seok Bo Song;Myeong Eun Choi;Ji Young Kim;Sang Ik Han
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.68 no.4
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    • pp.327-334
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    • 2023
  • The cultivation period of mung beans (Vigna radiata L.) in Korea has undergone recent variations. However, limited research has been conducted on pod shattering and sprout characteristics of mung beans on different sowing dates. This study aims to compare pod shattering and sprouts productivity based on different sowing dates. The research was was conducted with six different sowing dates (early May, mid-May, early June, mid-June, early July, and mid-July) in 2021 and 2022. Delayed sowing dates resulted in shortened days to germination, flowering time, and maturity time, whereas plant height, branch number, and node number increased. In addition, stem thickness and the number of pods per plant decreased. In the mung bean cultivar 'Sanpo', the pod shattering rate ranged from 10.0% to 19.3%, consistently lower than that of 'Dahyun' across all six sowing dates. The sowing date associated with the lowest shattering rate was early June. 'Sanpo' sown in early July and 'Dahyun' sown in mid-May exhibited the highest sprout production, at 871% and 750%, respectively.

Analysis of Private Road Toll Discounts and Subsidy Payment Plan for Sunset-type Vehicles (민자도로의 통행료 할인 현황과 일몰형 통행차량의 보조금 지급 방안)

  • Kim, Ji-Myong;Lim, Kwangk-kyun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.44 no.4
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    • pp.519-529
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    • 2024
  • Vehicle toll discounts on private roads are categorized into two types: non-sunset and sunset. Sunset types refer to provisions in which all or part of a law loses its effect upon a specific legislator-set deadline. Vehicles eligible for 'sunset' discounts include cargo vehicles operating late at night and eco-friendly vehicles powered by electricity or hydrogen. Korean government has subsidized all reduced toll fees for vehicles classified as non-sunset types on private roads to operators, but no subsidies have been provided for toll reductions on sunset vehicles. The rapid increase in electric hydrogen vehicles escalates the burden of reduced toll revenue on private road operators. This study analyzed traffic volume and toll reduction data from eight private road operators nationwide as of the end of 2023 to propose the necessity and method of supporting sunset-type toll reduction subsidies. In 2022, the subsidy for non-sunset types amounted to 87.5 billion won, or 18.6 % of total traffic revenue. The toll exemption and reduction ratio under the concession agreement ranged from 4.0 % to 5.65 % of total traffic volume for each operator. Although the proportion of vehicles exempted from sunset traffic increased from 0.85 % in 2017 to 2.79 % in 2022, the reduction amount ratio reached 4.2 % (KRW 25.5 billion) of total traffic revenue in 2022. The escalating number of registered eco-friendly vehicles is gradually causing operating profit losses on private roads. In alignment with the government's policy to expand eco-friendly vehicles, it is imperative to consider including vehicles eligible for toll reductions listed under the sunset category for subsidy payments. The study established a minimum ratio for toll reduction assistance at 4.0 %, agreed upon between the road authorities and private operators. Three policy alternatives were proposed to ensure preservation of amounts exceeding this threshold for sustaining adequate toll revenue for private road operators.

A Survey of the Status of Nutrition in Rural Korea (농촌(農村) 영양실태(營養實態)에 관(關)한 조사(調査))

  • Lee, Geum-Yeong;Suh, Myung-Sook
    • Journal of Nutrition and Health
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    • v.6 no.1
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    • pp.71-76
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    • 1973
  • 1. This survey is somewhat different from that conducted by Yonsei University, although being in many respects, very similar. We found the average per capita caloric intake to be 7 or 8% of what it should be. Of that caloric intake, 84.5% in the model village here and 82.2% in the compared village Bupyong, by and large depends on cereal grains. Since such grains tend to distend the stomach, the farmers, it seems,should substitute fat for a part of their diet so as to dimish digestive pain and still receive the necessary calories. 2. Protein is the most important nutrient for the development of physical strength and improvement of health, but the average daily intake is only 68.3% of the necessary amount. It is desirable that the ratio of vegetable protein to that of animal be one to three for maintaining one's health. Most of the villager's protein, however, comes from plants: the intake of animal protein, at a level of only 13.6 g, is far below such a one to three ratio. 3. In the model village, 497.6 mg, of inorganic calcium is the daily intake level. In the compared village it is 505.5 mg, making a difference of only 8mg. This, however, is 35% less than the recommended intake. More than 50% of this calcium comes from cereals and other plants. Moreover, plant calcium which has much oxakuc acud us not as nutritional as animal calcium, so their calcium diet is less than it would appear. We must, therefore, make efforts to receive as good nutritional calcium as possible. 4. Among the vitamin group, the daily average intake of vitamin A and vitamin $B_{2}$ are respectively 40% and 32% less than the desired intake, while vitamin $B_{1}$ happens to be taken in sufficient quantities and more niacin is taken than which is even necessary. The intake of vitamin C is much more than the necessary quantity. However, this figure was calculated from uncooked food; if the loss from cooking were to be considered, the real intake might well be a little less. Also, as this survey was carried out in May, some of these results were influenced by the fact that lettuce and spinach are seasonally popular. In conclusion, except for a few nutrients which are in abundance, the normal food intake in a day is, on the whole, less than the average recommended. Furthermore despite the fact that both of these places are model villages in the development of nutrition, it seems that they have not gotten out of such conventional eating habiys as the almost dependancy on cereal grains. Cow's milk, sheep's milk, eggs and so on produced by each farmhouse are not used for their own families but are taken to the market for the purpose of making money. Accordingly, I think from now we must seek to improve, guide and enlighten the farmers as to how to correct their eating habits and implement changes in their lives so that our firm purpose may be achieved.

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CELL CULTURE STUDIES OF MAREK'S DISEASE ETIOLOGICAL AGENT (조직배양(組織培養)에 의한 Marek 병(病) 병원체(病原體)의 연구(硏究))

  • Kim, Uh-Ho
    • Korean Journal of Veterinary Research
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    • v.9 no.1
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    • pp.23-62
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    • 1969
  • Throughout the studies the following experimental results were obtained and are summarized: 1. Multiplication of agents in primary cell cultures of both GF classical and CR-64 acute strain of Marek's disease infected chicken kidneys was accompanied by the formation of distinct transformed cell foci. This characteristic nature of cell transformation was passaged regularly by addition of dispersed cell from infected cultures to normal chicken kidney cell cultures, and also transferred was the nature of cell transformation to normal chick-embryo liver and neuroglial cell cultures. No cytopathic changes were noticed in inoculated chick-embryo fibroblast cultures. 2. The same cytopathic effects were noticed in normal kidney cell monolayers after the inoculation of whole blood and huffy coat cells derived from both forms of Marek's disease infected chickens. In these cases, however, the number of transformed cell foci appearing was far less than that of uninoculated monolayers prepared directly from the kidneys of Marek's disease infected chickens. 3. The change in cell culture IS regarded as a specific cell transformation focus induced by an oncogenic virus rather than it plaque in slowly progressing cytopathic effect by non-oncogenic viruses, and it is quite similar to RSV focus in chick-embryo fibroblasts in many respects. 4. The infective agent (cell transformable) were extremely cell-associated and could not be separated in an infective state from cells under the experimental conditions. 5. The focus assay of these agents was valid as shown by the high degree of linear correlation (r=0.97 and 0.99) between the relative infected cell concentration (in inoculum) and the transformed cell foci counted. 6. No differences were observed between the GF classical strain and the CR-64 acute strain of Marek's disease as far as cell culture behavior. 7. Characterization of the isolates by physical and chemical treatments, development of internuclear inclusions in Infected cells, and nucleic acid typing by differential stainings and cytochemical treatments indicated that the natures of these cell transformation agents closely resemble to those described fer the group B herpes viruses. 8. Susceptible chicks inoculated with infected kidney tissue culture cells developed specific lesions of Marek's disease, and in a case of prolonged observation after inoculation (5 weeks) the birds developed clinical symptoms and gross lesions of Marek's disease. Kidney cell cultures prepared from those inoculated birds and sacrificed showed a superior recovery of cell transformation property by formation of distinct foci. 9. Electron microscopic study of infected kidney culture cells (GF agent) by negative staining technique revealed virus particles furnishing the properties of herpes viruses. The particle was measured about $100m{\mu}$ and, so far, no herpes virus envelop has been seen from these preparations. 10. No relationship of both isolates to avian leukosis/sarcoma group viruses and PPLO was observed.

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