• Title/Summary/Keyword: Surface process

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Changes of Mineralogical Characteristics of Precipitates in Acid Mine Drainage of the Dalsung Mine and Related Changes of Trace Elements (달성광산 산성광산배수 침전물의 시간에 따른 광물상 특성 변화 및 이에 따른 미량원소의 거동 변화)

  • Yoon, Young Jin;Kim, Yeongkyoo;Lee, Seong-joo
    • Economic and Environmental Geology
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    • v.55 no.5
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    • pp.531-540
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    • 2022
  • Various iron minerals that precipitate in acid mine drainage have a great influence on the concentration change and mobility of trace elements in the drainage during phase transition to other minerals as well as the precipitation process. This study investigated the change of mineral properties and the behaviors of trace elements influenced by pH and time for the precipitates collected from the acid mine drainage treatment system of the Dalsung mine, where schwertmannite is mainly precipitated. However, the main mineral precipitated in the drainage was goethite, suggesting schwetmannite has already undergone a phase transition to goethite to some extent, and it was observed that at higher pH, the peak width at half maximum of XRD peak was narrower. This can be interpreted as the transformation of small amount of amorphous schwetmannite to goethite or an increase in the crystallinity of goethite, and it showed that the higher the pH, the greater this change was. The concentration of Fe was also greatly affected by the pH values, and as the pH increased, the concentration of Fe in the drainage decreased. With increasing time, the Fe concentration increased and then decreased, which can be interpreted to indicate the dissolution of schwertmannite and precipitation of goethite. This mineral change probably resulted in the rapid increase of the concentration of S at initial stage, but its concentration was stabilized later. The concentration of S is also related to the stability of schwetmannite, showing a high concentration at a low pH at which schwertmannite is stable and a low concentration at a high pH at which goethite is stable. The trace elements present as cations in the drainage also showed a close relationship with the pH, generally the lower the pH, the higher the concentration, due to the solubility changes by the pH, and the precipitation and the changes in mineral surface charge at high pH. On the other hand, in the case of As, existing as an anion, although it showed a high concentration at low pH, its concentration increased with time at all pH values, which is probably related to the concentration of Fe which can be coprecipitated in the drainage, and the increase of As concentration with time is also considered to be related to the decrease in schwertmannite rather than the mineral surface charge.

Daesoonjinrihoe from both Superficial Religious Perspectives and Deep Religious Perspectives : Focused on Religious Experience (표층과 심층의 시각에서 바라본 대순진리회 - 종교적 경험의 관점에서 -)

  • Lee, Eun-hui
    • Journal of the Daesoon Academy of Sciences
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    • v.27
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    • pp.245-282
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    • 2016
  • Currently, the whole world is being swept away by spiritual movements seeking divinity in oneself. Yet there are terror attacks, religious disputes and other conflicts continuously taking place on larger and larger scales as well as expanding further and further throughout the world. Interreligious harmony seems like a distant ideal. What is the ultimate cause of religious conflicts? Is interreligious communication truly that difficult? Even among different cultures, said cultures' varieties of ritual expressions, and various religious doctrines, there are points of general common to be appreciated if a deep perspective is adopted. When we find the common ground and understand each other's difference, it will be easier to communicate since everyone will be learning from each other. What could serve as common ground for different religions? Many scholars speak about the state of 'oneness' that is claimed by mysticism throughout a large array of religions. This state of oneness is typically not achieved overnight, but it serves as a prospective state which is pluralistically inclusive. This "religion of enlightenment" emphasizes the process of reaching comprehensive interreligious agreement would be characterized by a deep religious perspective. If superficial religious perspectives focuses only on faith to attain blessings and engage in blind belief, then, by contrast, deep religious perspectives emphasize inner divinity, the true self, orthe higher self. The words, 'superficial religious perspective' and 'deep religious perspective' were defined for personal convenience by O Gang-nam, a scholar of comparative religion. Consequently, this classification is a relative binary concept lacking hard and fast rules with regards to distinctions. But the concept of superficial religious perspectives and deep religious perspectives has its advantage in allowing clearer and easier discussion about religions because it could embrace all aspects of religious life and the development of various religious sentiment. In this way, the terms surface religious perspectives and deep religious perspectives will be used in limited framework. I both borrow this concept and reconsider it by referring to other scholars' methods of classification. From that point, I explore and these views in relation to religious experience. How does religiosity develop, maturity of religious faith take place, deep awareness of truth reveal itself, or an attitude of open-mindedness arise? After these states are realized, is interreligious agreement possible? Most religious studies scholars point out 'religious experience.' They say people could develop their faith from superficial religious beliefs into a more mature and deeper faith through religious experience while continuously aspiring towards enlightenment and practicing their religion in daily life. This study will try to examine aspects of superficial religious perspectives and deep religious perspectives represented in each religion and also explore criticism of each religion. With this view of superficial religious perspectives and deep religious perspectives, some cases documenting the religious experience of Daesoonjinrihoe disciples will be analyzed to see how their religiosity develops from superficial religious perspectives into deep religious perspectives through certain religious experiences. The characteristics of those experiences will also be investigated.

The Accuracy Evaluation of Digital Elevation Models for Forest Areas Produced Under Different Filtering Conditions of Airborne LiDAR Raw Data (항공 LiDAR 원자료 필터링 조건에 따른 산림지역 수치표고모형 정확도 평가)

  • Cho, Seungwan;Choi, Hyung Tae;Park, Joowon
    • Journal of agriculture & life science
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    • v.50 no.3
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    • pp.1-11
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    • 2016
  • With increasing interest, there have been studies on LiDAR(Light Detection And Ranging)-based DEM(Digital Elevation Model) to acquire three dimensional topographic information. For producing LiDAR DEM with better accuracy, Filtering process is crucial, where only surface reflected LiDAR points are left to construct DEM while non-surface reflected LiDAR points need to be removed from the raw LiDAR data. In particular, the changes of input values for filtering algorithm-constructing parameters are supposed to produce different products. Therefore, this study is aimed to contribute to better understanding the effects of the changes of the levels of GroundFilter Algrothm's Mean parameter(GFmn) embedded in FUSION software on the accuracy of the LiDAR DEM products, using LiDAR data collected for Hwacheon, Yangju, Gyeongsan and Jangheung watershed experimental area. The effect of GFmn level changes on the products' accuracy is estimated by measuring and comparing the residuals between the elevations at the same locations of a field and different GFmn level-produced LiDAR DEM sample points. In order to test whether there are any differences among the five GFmn levels; 1, 3, 5, 7 and 9, One-way ANOVA is conducted. In result of One-way ANOVA test, it is found that the change in GFmn level significantly affects the accuracy (F-value: 4.915, p<0.01). After finding significance of the GFmn level effect, Tukey HSD test is also conducted as a Post hoc test for grouping levels by the significant differences. In result, GFmn levels are divided into two subsets ('7, 5, 9, 3' vs. '1'). From the observation of the residuals of each individual level, it is possible to say that LiDAR DEM is generated most accurately when GFmn is given as 7. Through this study, the most desirable parameter value can be suggested to produce filtered LiDAR DEM data which can provide the most accurate elevation information.

Predicting the Effects of Rooftop Greening and Evaluating CO2 Sequestration in Urban Heat Island Areas Using Satellite Imagery and Machine Learning (위성영상과 머신러닝 활용 도시열섬 지역 옥상녹화 효과 예측과 이산화탄소 흡수량 평가)

  • Minju Kim;Jeong U Park;Juhyeon Park;Jisoo Park;Chang-Uk Hyun
    • Korean Journal of Remote Sensing
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    • v.39 no.5_1
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    • pp.481-493
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    • 2023
  • In high-density urban areas, the urban heat island effect increases urban temperatures, leading to negative impacts such as worsened air pollution, increased cooling energy consumption, and increased greenhouse gas emissions. In urban environments where it is difficult to secure additional green spaces, rooftop greening is an efficient greenhouse gas reduction strategy. In this study, we not only analyzed the current status of the urban heat island effect but also utilized high-resolution satellite data and spatial information to estimate the available rooftop greening area within the study area. We evaluated the mitigation effect of the urban heat island phenomenon and carbon sequestration capacity through temperature predictions resulting from rooftop greening. To achieve this, we utilized WorldView-2 satellite data to classify land cover in the urban heat island areas of Busan city. We developed a prediction model for temperature changes before and after rooftop greening using machine learning techniques. To assess the degree of urban heat island mitigation due to changes in rooftop greening areas, we constructed a temperature change prediction model with temperature as the dependent variable using the random forest technique. In this process, we built a multiple regression model to derive high-resolution land surface temperatures for training data using Google Earth Engine, combining Landsat-8 and Sentinel-2 satellite data. Additionally, we evaluated carbon sequestration based on rooftop greening areas using a carbon absorption capacity per plant. The results of this study suggest that the developed satellite-based urban heat island assessment and temperature change prediction technology using Random Forest models can be applied to urban heat island-vulnerable areas with potential for expansion.

Scientific Study on Clepsydra of Changgyeonggung Palace, National Treasure for Diagnosis on State of Conservation (국보 창경궁 자격루 누기의 보존상태 진단을 위한 과학적 조사)

  • YOU Harim;LEE Jaesung;YU Jia;JO Hanui;PARK Younghwan;RYU Dongwan
    • Korean Journal of Heritage: History & Science
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    • v.56 no.3
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    • pp.138-156
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    • 2023
  • Some of the metal cultural heritage that make up a considerable proportion of Korea's cultural heritage have been installed and displayed outdoors due to their own functions, roles, and scale. Therefore, more diverse and complex damages can occur outdoors than they are in a stable environment. Therefore, it is necessary to combine accurate diagnosis and systematic survey methods in order to utilize basic data obtained from research results as data for the long-term and continuous conservation management as well as to do the research to diagnose the conservation status of outdoor cultural heritage. The clepsydra(hereinafter referred to as Jagyeongnu) of Changgyeonggung Palace, the National Treasure has been installed and displayed outdoors since it was manufactured. Though regular conservation and maintenance of the Jagyeongnu have been carried out, damage still occurred. Therefore, the scientific research on Jagyeongnu to diagnose the state of conservation was conducted prior to the full-scale conservation treatment. First, the state of conservation was investigated with an examination of basic data, macroscopic inspections and past records of repair history according to the purpose of the research. More detailed examinations were also conducted through the 3D scan, surface pattern investigation, and color difference analysis, and the analysis on materials and contaminants were conducted through P-XRF, FT-IR, and Py-GC/MS. The scientific research reveals that squalane and silicone oil have been applied in the past for conservation treatment and directly exposed to outdoor environmental factors, which caused damage to Jagyeongnu and contaminants such as dust adhered thickly to its surface, accelerating severe damage. A greater incidence of damage was found around the part with relatively high exposure effect, which corresponded with the tendency identified by grouping color difference data. As a result of integrating various research methodologies to diagnose the state of conservation and secure basic data, the causes and types of damage were identified. Furthermore, the process of obtaining digital data to be utilized in various ways, and the color difference analysis presenting visible damage as scientific data and identifying the tendency of damage patterns were confirmed to have been effective.

Rare-Earth Metal Complex-Functionalized Mesoporous Silica for a Potential UV Sensor (잠재적인 UV 센서를 위한 희토류 금속착물이 기능화된 메조다공성 실리카)

  • Sung Soo Park;Mi-Ra Kim;Weontae Oh;Yedam Kim;Yeeun Lee;Youngeon Lee;Kangbeom Ha;Dojun Jung
    • Journal of Adhesion and Interface
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    • v.24 no.4
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    • pp.136-142
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    • 2023
  • In this study, TEOS was used as a silica source, and a triblock copolymer (P123) was used as a template to produce mesoporous silica with a well-ordered hexagonal mesopore array through a self-assembly method and hydrothermal process under acidic condition. (Surfactant-extracted SBA-15). Surfactant-extracted SBA-15 showed the particle shape of a short rod with a size of approximately 980 nm. The surface area and pore diameter were 730 m2g-1 and 70.8 Å, respectively. Meanwhile, aminosilane (3-aminopropyltriethoxysilane, APTES) was grafted into the mesopores using a post-synthesis method. Mesoporous silica (APTES-SBA-15) modified with aminosilane had a well-ordered pore structure (p6mm) and well-maintained the particle shape of short rods. The surface area and pore diameter of APTES-SBA-15 decreased to 350 m2g-1 and 60.7 Å, respectively. APTES-modified mesoporous silica was treated with a solution of rare earth metal ions (Eu3+, Tb3+) to synthesize a mesoporous silica material in which rare earth metal complexes were introduced into the mesopores. (Eu/APTES-SBA-15, Tb/APTES-SBA-15) These materials exhibited characteristic photoluminescence spectra by λex=250 nm. (5D47F5 (543.5 nm), 5D47F4 (583.5 nm), 5D47F3 (620.2 nm) transitions for Tb/APTES-SBA-15; 5D07F0 (577.7 nm), 5D07F1 (592.0 nm), 5D07F2 (614.9 nm), 5D07F3 (650.3 nm) and 5D07F4 (698.5 nm) transitions for Eu/APTES-SBA-15)

The Effects of Leukocyte Depleted Priming Solution on the Gastric Mucosal $Co_{2}$ Partial Pressure and Serum IL-8 Level during Cardiopulmonary Bypass in Korean Mongrel Dogs (한국산 잡견에서 백혈구 제거 충진액이 체외순환 중 위점막 이산화탄소 농도와 IL-8 수준에 미치는 영향)

  • Park Kuhn;Lee Jong Ho;Kim Jin Ho;Jin Ung;Kwon Jong Bum;Kim Chi Kyeong;Wang Young Pil
    • Journal of Chest Surgery
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    • v.38 no.12 s.257
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    • pp.807-814
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    • 2005
  • Background: Cardiopulmonary bypass is an essential process to maintain circulation for saving life during the cardiac surgery, But it is a process in which systemic inflammation was evoked inevitably because of the exposure of blood to foreign surface. The injuries to distal organs during the cardiopulmonary bypass were resulted from systemic inflammation and the disturbances of micro-circulations in the organs. We designed this study to research the effects of leukocyte depletion from pump-oxygenator priming solution on the systemic inflammation, and the micro-circulation of gastric mucosa that is suggested by the gastric mucosal $CO_{2}$ partial pressure and acidity. Material and Method: The dogs were divided into three groups according to the different pump-oxygenator priming solutions; non-hemic crystalloid solution; leukocyte-depleted homologous blood; and non leukocyte-depleted homo-logous blood. Each priming solution group contained five dogs. In all three groups, 2 hours of cardiopulmonary bypass, and 4 consecutive hours of general anesthesia was maintained on the mechanical ventilation. Each dog was evaluated for the gastric mucosal pH, $CO_{2}$ partial Pressure, arterial pH, $CO_{2}$ partial pressure, the exhaled air $CO_{2}$ partial pressure and the level of IL-8 on before the cardiopulmonary bypass, 1 hour after the cardiopulmonary bypass, 2 hours after the cardiopulmonary bypass, 2 hours after the restoration of normal circulation, and 4 hours after the restoration of normal circulation after the cardiopulmonary bypass. The levels of IL-8 were measured with ELISA (enzyme linked immunosorbent assay) technique. Result: 1. There were significant differences of gastric mucosal $CO_{2}$ partial pressure between the leukocyte-depleted homologous blood group and other two groups(vs non leukocyte-depleted homologous blood group; P=0.02, vs non-hemic crystalloid solution group; P=0,01). 2. The gastric mucosal pH of leukocyte-depleted homologous blood group was significantly different from non leukocyte-depleted homologous blood group (p=0.01). 3. The levels of IL-8, which examine the systemic inflammation, showed signi- ficantly better results in leukocyte-depleted homologous blood group and non-hemic crystalloid solution group than non leukocyte-depleted homologous blood group (p=0.01, 0.01). Conclusion: Based upon these results, we concluded that the leukocyte depletion from the pump-oxygenator priming solution has a beneficial effects in reducing systemic inflammation and the preserving of gastric mucosal micro-circulation.

Optimization of Microwave-Assisted Process for Extraction of Effective Components from Mosla dinthera M. (마이크로파 추출공정에 의한 쥐깨풀 유용성분의 추출조건 최적화)

  • Lee Eun-Jin;Kwon Young-Ju;Noh Jung-Eun;Lee Jeong-Eun;Lee Sung-Ho;Kim Jae-Keun;Kim Kwang-Soo;Choi Yong-Hee;Kwon Joong-Ho
    • Food Science and Preservation
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    • v.12 no.6
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    • pp.617-623
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    • 2005
  • Response surface methodology (RSM) was applied to microwave-assisted process (MAP) extraction for effective components from Mosla dianthera M. Microwave power (2,450 MHz, 0-160 W) and extraction time (1-5 min) were used as independent variables ($X_i$) for central composite design to yield 10 different extraction conditions. Optimum conditions were predicted for dependent variables of $75\%$ ethanol extracts, such as total yield($Y_1$), total phenolics($Y_2$), total flavonoids($Y_3$), and electron donation ability($Y_4$, EDA). Determination coefficients ($R^2$) of regression equations for dependent variables ranged from 0.8397 to 0.9801, and microwave power was observed to be more influential than extraction time in MAP. The maximal values of each dependent variable predicted at different extraction conditions of microwave power (W) and extraction time (min) were as follows; $6.76\%$ of total yield at 142.00 W and 4.36 min, 78.68 mg/g of total phenolics at 136.78 W and 4.40 min, 6.75 mg/g of total flavonoids at 159,69 W and 3.17 min, and $49.81\%$ of EDA at 133.87 W and 4.47 min, respectively. The superimposed contour maps for maximizing dependent variables illustrated the MAP conditions of 79 to 113 W in power and of 2.73 to 3.84 min in extraction time.

Bottom electrode optimization for the applications of ferroelectric memory device (강유전체 기억소자 응용을 위한 하부전극 최적화 연구)

  • Jung, S.M.;Choi, Y.S.;Lim, D.G.;Park, Y.;Song, J.T.;Yi, J.
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.8 no.4
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    • pp.599-604
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    • 1998
  • We have investigated Pt and $RuO_2$ as a bottom electrode for ferroelectric capacitor applications. The bottom electrodes were prepared by using an RF magnetron sputtering method. Some of the investigated parameters were a substrate temperature, gas flow rate, RF power for the film growth, and post annealing effect. The substrate temperature strongly influenced the surface morphology and resistivity of the bottom electrodes as well as the film crystallographic structure. XRD results on Pt films showed a mixed phase of (111) and (200) peak for the substrate temperature ranged from RT to $200^{\circ}C$, and a preferred (111) orientation for $300^{\circ}C$. From the XRD and AFM results, we recommend the substrate temperature of $300^{\circ}C$ and RF power 80W for the Pt bottom electrode growth. With the variation of an oxygen partial pressure from 0 to 50%, we learned that only Ru metal was grown with 0~5% of $O_2$ gas, mixed phase of Ru and $RuO_2$ for $O_ 2$ partial pressure between 10~40%, and a pure $RuO_2$ phase with $O_2$ partial pressure of 50%. This result indicates that a double layer of $RuO_2/Ru$ can be grown in a process with the modulation of gas flow rate. Double layer structure is expected to reduce the fatigue problem while keeping a low electrical resistivity. As post anneal temperature was increased from RT to $700^{\circ}C$, the resistivity of Pt and $RuO_2$ was decreased linearly. This paper presents the optimized process conditions of the bottom electrodes for memory device applications.

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THE EARLY EFFECTS OF SODIUM FLUORIDE ON THE RAPID PALATAL EXPANSION IN GROWING DOGS (유성견의 정중구개봉합 급속확대시 투여된 불화나트륨의 초기 효과에 관한 연구)

  • Lee, Hyun-Kyung;Chung, Kyu-Rhim
    • The korean journal of orthodontics
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    • v.28 no.1 s.66
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    • pp.85-97
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    • 1998
  • The purpose of this study was to observe the effects of sodium fluoride on the bony repair and regeneration processes after the rapid palatal expansion in the growing dogs. Eighteen dogs were divided into experimental and control groups. They were in the late mixed dentition. The rapid Palatal expansion was undertaken in all the animals($180^{\circ}$ turn/day) for ten days. The animals were sacrificed on 0, 15 and 45 days after the finish of expansion. One mg NaF/kg of body weight/day were given orally to the experimental group. Blood samples were drawn before and after expansion and the se겨m calcium, phosphate and alkaline phosphatase level were measured. The undecalcified bone section of midpalatal suture area was made, and observed under the light microscopy The results were as follows ; 1. The day after expansion, the infiltration of inflammatory cells were prominent and the new bone formation started at the edges of the two palatal plates bodering the midpalatal suture in both groups. Especially, the newly formed osteoid were very extensive and the osteoblasts lining the osteoid were very active in the experimental group. 2. At fifteen days after expansion, the active osteoblasts lining the osteold at the surface of trabecular bony spicules and active new bone formation were observed in the both groups. However, the cellular activity and new bone formation were more prominent In the experimental group. 3. At forty five days after expansion, the continuous osteoid and new bone formation and active osteoblasts were observed in the experimental group. But these phenomena were not observed in the control group. In the control group, the numerous osteoclasts were adjacent midpalatal suture and the bony remodeling process was begun. The serum alkaline phosphatase level was maintained highly in the experimental group, but decreased in the control. According to the above results, the author reached the conclusion that sodium fluoride has the stimulation effects on the osteoid production of the osteoblasts during the healing process after the rapid Palatal expansion more continuously.

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