• 제목/요약/키워드: Support ring

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Palaeomagnetism of Cretaceous Rocks in the Ǔisǒng Area, Kyǒngsang Basin, Korea (의성지역 백악기 암석에 대한 고자기 연구)

  • Kim, In-Soo;Lee, Hyun Koo;Yun, Hyesu;Kang, Hee-Cheol
    • Economic and Environmental Geology
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    • v.26 no.3
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    • pp.403-420
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    • 1993
  • The Cretaceous Kyongsang Basin is known to be composed of several tectonic blocks (or subbasins) with each distinct stratigraphic succession. The study area represents a major part of one of these blocks, i. e. the $\check{U}is\check{o}ng$ block. The area is charaterized by a suite of WNW-trending sinistral strike-slip faults as well as a number of ring faults. A total of 292 independently oriented core samples were drilled from 23 sites, covering virtually all the formations of the Cretaceous $Ky\check{o}ngsang$ Supergroup. Alternating field and thermal demagnetization experiments were conducted to reveal the primary magnetization. Due to the homoclinal nature of the strata in the area, it was not possible to make use of the conventional fold test It is, however, believed that the primary remanent components have been obtained from the majority of the formations, considering the similarity of the palaeomagnetic pole positions with those of contemporary strata of other blocks and the existence of antiparallel reversed remanence. It was found neither any significant difference in magnetic declination on each side of the strike-slip faults nor systematic change of magnetic declination with distance from the fault-line. This does not support such a block rotation hypothesis associated with the strike-slip faulting in the area as alleged by some authors. The samples from the outcrops on or near the fault-lines were severely overprinted by the recent magnetic fields regardless of age and lithology. Epithermal Au-Ag-Cu-Pb-Zn mineralizations are known along some fault lines in the area. It is interpreted that these two facts are closely related with fluid circulations along the fracture zones caused by fault activities. In regard to the age of the strata as deduced from the magnetostratigraphic consideration, the $Ch\check{o}mgok$ formation and the lower strata should be older than Barremian or 124 Ma. The age of volcanics of the $Yuch^{\prime}\check{o}n$ Group sampled in this study should be younger than Campanian or 83 Ma.

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Spatio-temporal Analysis of Freeway Emissions for Establishing Public Health Policies Based on Transportation (교통기반 공공보건 정책 수립을 위한 고속도로 차량배출가스 시공간 패턴분석)

  • LEE, Seol Young;JOO, Shinhye;YOUN, Seok Min;OH, Cheol
    • Journal of Korean Society of Transportation
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    • v.34 no.5
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    • pp.377-393
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    • 2016
  • Vehicle emissions have been known as a critical factor to give a negative impact on the public health. In particular, particulate matters(PM) and NOx are highly related with respiratory diseases such as asthma. This study aimed at analyzing spatio-temporal patterns of PM and NOx generated from urban freeway traffic. MOVES, which is a well-known emission analysis tool presented by US Environmental Protection Agency(EPA), was applied to estimate PM and NOx based on traffic volume and speed data obtained from Seoul Outer Ring Expressway during January~June, 2012. K-means clustering analysis was used for categorizing the Level of Vehicle Emissions(LOVE) to support more systematical identification of the significance of emissions. Then, spatio-temporal analyses of estimated emissions were conducted by LOVE. Finally, this study proposed a set of strategies to reduce both PM and NOx to enhance public health based on analysis results.

Superoxide and Nitric Oxide Involvement in Enhancing of N-methyl-D-aspartate Receptor-Mediated Central Sensitization in the Chronic Post-ischemia Pain Model

  • Ryu, Tae-Ha;Jung, Kyung-Young;Ha, Mi-Jin;Kwak, Kyung-Hwa;Lim, Dong-Gun;Hong, Jung-Gil
    • The Korean Journal of Pain
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    • v.23 no.1
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    • pp.1-10
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    • 2010
  • Background: Recent studies indicate that reactive oxygen species (ROS) are involved in persistent pain, including neuropathic and inflammatory pain. Since the data suggest that ROS are involved in central sensitization, the present study examines the levels of activated N-methyl-D-aspartate (NMDA) receptors in the dorsal horn after an exogenous supply of three antioxidants in rats with chronic post-ischemia pain (CPIP). This serves as an animal model of complex regional pain syndrome type-I induced by hindpaw ischemia/reperfusion injury. Methods: The application of tight-fitting O-rings for a period of three hours produced CPIP in male Sprague-Dawley rats. Allopurinol 4 mg/kg, allopurinol 40 mg/kg, superoxide dismutase (SOD) 4,000 U/kg, N-nitro-L-arginine methyl ester (L-NAME) 10 mg/kg and SOD 4,000 U/kg plus L-NAME 10 mg/kg were administered intraperitoneally just after O-ring application and on the first and second days after reperfusion. Mechanical allodynia was measured, and activation of the NMDA receptor subunit 1 (pNR1) of the lumbar spinal cord (L4-L6) was analyzed by the Western blot three days after reperfusion. Results: Allopurinol reduced mechanical allodynia and attenuated the enhancement of spinal pNR1 expression in CPIP rats. SOD and L-NAME also blocked spinal pNR1 in accordance with the reduced mechanical allodynia in rats with CPIP. Conclusions: The present data suggest the contribution of superoxide, produced via xanthine oxidase, and the participation of superoxide and nitric oxide as a precursor of peroxynitrite in NMDA mediated central sensitization. Finally, the findings support a therapeutic potential for the manipulation of superoxide and nitric oxide in ischemia/reperfusion related pain conditions.

A Hierarchical Server Structure for Parallel Location Information Search of Mobile Hosts (이동 호스트의 병렬적 위치 정보 탐색을 위한 서버의 계층 구조)

  • Jeong, Gwang-Sik;Yu, Heon-Chang;Hwang, Jong-Seon
    • Journal of KIISE:Computer Systems and Theory
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    • v.28 no.1_2
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    • pp.80-89
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    • 2001
  • The development in the mobile computing systems have arisen new and previously unforeseen problems, such as problems in information management of mobile host, disconnection of mobile host and low bandwidths of wireless communications. Especially, location information management strategy of mobile host results in an increased overhead in mobile computing systems. Due to the mobility of the mobiles host, the changes in the mobile host's address depends on the mobile host's location, and is maintained by mapping physical address on virtual address, Since previously suggested several strategies for mapping method between physical address and virtual address did not tackle the increase of mobile host and distribution of location information, it was not able to support the scalability in mobile computing systems. Thus, to distribute the location inrormation, we propose an advanced n-depth LiST (Location information Search Tree) and the parallel location search and update strategy based on the advanced n-depth LiST. The advanced n-depth LiST is logically a hierarchical structure that clusters the location information server by ring structure and reduces the location information search and update cost by parallel seatch and updated method. The experiment shows that even though the distance of two MHs that communicate with each other is large, due to the strnctural distribution of location information, advanced n-depth LiST results in good performance. Moreover, despite the reduction in the location information search cost, there was no increase in the location information update cost.

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Digit ratio(2D:4D) and gender role orientation in health and medical students (보건의료 대학생의 손가락 길이비(2D:4D)와 성역할 정체감)

  • Kim, Keum-Sook;Cho, Keun-Ja
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.5
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    • pp.2170-2177
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    • 2012
  • The ratio of index finger length to ring finger length(2D:4D) is an index of prenatal testosterone and/or estrogen exposure. The aim of this study is to investigate digit ratio and the type of gender-role orientation, to identify the correlation between 2D:4D and gender-role orientation in health and medical students. Participants were 120 male and 146 female university students majoring in health or medicine. After filling in KSRI(Korean Sex Role Inventory), 2nd and 4th finger lengths were measured on both hands using vernier callipers with photocopy. This study showed 2D:4D in the males was 0.95, and that in the females was 0.96 (p<0.01). 38.3% male students revealed androgyny, on the other hand, 35.6% female students revealed undifferentiated type from KSRI. And also, there was a significant difference in masculinity score between male and female but not in feminity score. There was no significant difference in 2D:4D according gender role orientation. The KSRI masculinity score was negatively related to 2D:4D of left hand in male (p<0.05). The results of this study suggest that a more masculine gender role orientation in males is associated with low 2D:4D revealing higher testosterone and/or lower estrogen level in utero. However, more research in 2D:4D ratio to Korean is needed for support of this result.

Studies of Solvolyses of Biphenyl-4-carbonyl Chloride by Extended Grunwald-Winstein Equation (확장된 Gruwald-Winstein 식에 의한 Biphenyl-4-carbonyl chloride의 가용매분해 반응대한 연구)

  • Choi, Hojune;Koh, HanJoong;Yang, Kiyull;Koo, InSun
    • Journal of the Korean Chemical Society
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    • v.60 no.1
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    • pp.16-20
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    • 2016
  • The solvolysis rate constants of biphenyl-4-carbonyl chloride (C6H5C6H5COCl, 1) in 19 different solvents are well correlated with the extended Grunwald-Winstein equation, using the NT solvent nucleophilicity scale, YCl solvent ionizing scale, and I aromatic ring parameter with sensitivity values of 0.31±0.10, 0.46±0.05, and 0.96±0.20 for l, m, and h, respectively. These l, m, and h values can be considered to support a dissciative SN2 reaction pathway. This interpretation is further supported by the activation parameters, i.e., relatively small positive ΔH (15.3~16.1 kcal/mol) values and large negative ΔS (−17.2~−20.0 cal/mol·K) values.

Geotechnical Engineering Progress with the Incheon Bridge Project

  • Cho, Sung-Min
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.09a
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    • pp.133-144
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    • 2009
  • Incheon Bridge, 18.4 km long sea-crossing bridge, will be opened to the traffic in October 2009 and this will be the new landmark of the gearing up north-east Asia as well as the largest & longest bridge of Korea. Incheon Bridge is the integrated set of several special featured bridges including a magnificent cable-stayed girder bridge which has a main span of 800 m width to cross the navigation channel in and out of the Port of Incheon. Incheon Bridge is making an epoch of long-span bridge designs thanks to the fully application of the AASHTO LRFD (load & resistance factor design) to both the superstructures and the substructures. A state-of-the-art of the geotechnologies which were applied to the Incheon Bridge construction project is introduced. The most Large-diameter drilled shafts were penetrated into the bedrock to support the colossal superstructures. The bearing capacity and deformational characteristics of the foundations were verified through the world's largest static pile load test. 8 full-scale pilot piles were tested in both offshore site and onshore area prior to the commencement of constructions. Compressible load beyond 30,000 tonf pressed a single 3 m diameter foundation pile by means of bi-directional loading method including the Osterberg cell techniques. Detailed site investigation to characterize the subsurface properties had been carried out. Geotextile tubes, tied sheet pile walls, and trestles were utilized to overcome the very large tidal difference between ebb and flow at the foreshore site. 44 circular-cell type dolphins surround the piers near the navigation channel to protect the bridge against the collision with aberrant vessels. Each dolphin structure consists of the flat sheet piled wall and infilled aggregates to absorb the collision impact. Geo-centrifugal tests were performed to evaluate the behavior of the dolphin in the seabed and to verify the numerical model for the design. Rip-rap embankments on the seabed are expected to prevent the scouring of the foundation. Prefabricated vertical drains, sand compaction piles, deep cement mixings, horizontal natural-fiber drains, and other subsidiary methods were used to improve the soft ground for the site of abutments, toll plazas, and access roads. Light-weight backfill using EPS blocks helps to reduce the earth pressure behind the abutment on the soft ground. Some kinds of reinforced earth like as MSE using geosynthetics were utilized for the ring wall of the abutment. Soil steel bridges made of corrugated steel plates and engineered backfills were constructed for the open-cut tunnel and the culvert. Diverse experiences of advanced designs and constructions from the Incheon Bridge project have been propagated by relevant engineers and it is strongly expected that significant achievements in geotechnical engineering through this project will contribute to the national development of the longspan bridge technologies remarkably.

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Hydrogenation of Polycyclic Aromatic Hydrocarbons Over Pt/Kieselguhr Catalysts in a Trickle Bed Reactor (Trickle Bed Reactor에서 Pt/Kieselguhr 촉매를 이용한 다환방향족 탄화수소 수소화 반응)

  • Seung Kyo, Oh;Seohyeon, Oh;Gi Bo, Han;Byunghun, Jeong;Jong-Ki, Jeon
    • Clean Technology
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    • v.28 no.4
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    • pp.331-338
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    • 2022
  • The objective of this study is to prepare bead-type and pellet-type Pt (1 wt%)/Kieselguhr catalysts as hydrogenation catalysts for the polycyclic aromatic hydrocarbons (PAHs) included in pyrolysis fuel oil (PFO). The optimal reaction temperature to maximize the yield of saturated cyclic hydrocarbons during the PFO-cut hydrogenation reaction in a trickle bed reactor was determined to be 250 ℃. A hydrogen/PFO-cut flow rate ratio of 1800 was found to maximize 1-ring saturated cyclic compounds. The yield of saturated cyclic compound increased as the space velocity (LHSV) of PFO-cut decreased. The difference in hydrogenation reaction performance between the pellet catalyst and the bead catalyst was negligible. However, the catalyst impregnated by Pt after molding the Kieselguhr support (AI catalyst) showed higher hydrogenation activity than the catalyst molded after Pt impregnation on the Kieselguhr powder (BI catalyst), which was a common phenomenon in both the pellet catalysts and bead catalysts. This may be due to a higher number of active sites over the AI catalyst compared to the BI catalyst. It was confirmed that the pellet catalyst prepared by the AI method had the best reaction activity of the prepared catalysts in this study. The majority of the PFO-cut hydrogenation products were cyclic hydrocarbons ranging from C8 to C15, and C11 cyclic hydrocarbons had the highest distribution. It was confirmed that both a cracking reaction and hydrogenation occurred, which shifted the carbon number distribution towards light hydrocarbons.

Analysis of Potential Infection Site by Highly Pathogenic Avian Influenza Using Model Patterns of Avian Influenza Outbreak Area in Republic of Korea (국내 조류인플루엔자 발생 지역의 모델 패턴을 활용한 고병원성조류인플루엔자(HPAI)의 감염가능 지역 분석)

  • EOM, Chi-Ho;PAK, Sun-Il;BAE, Sun-Hak
    • Journal of the Korean Association of Geographic Information Studies
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    • v.20 no.2
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    • pp.60-74
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    • 2017
  • To facilitate prevention of highly pathogenic avian influenza (HPAI), a GIS is widely used for monitoring, investigating epidemics, managing HPAI-infected farms, and eradicating the disease. After the outbreak of foot-and-mouth disease in 2010 and 2011, the government of the Republic of Korea (ROK) established the GIS-based Korean Animal Health Integrated System (KAHIS) to avert livestock epidemics, including HPAI. However, the KAHIS is not sufficient for controlling HPAI outbreaks due to lack of responsibility in fieldwork, such as sterilization of HPAI-infected poultry farms and regions, control of infected animal movement, and implementation of an eradication strategy. An outbreak prediction model to support efficient HPAI control in the ROK is proposed here, constructed via analysis of HPAI outbreak patterns in the ROK. The results show that 82% of HPAI outbreaks occurred in Jeolla and Chungcheong Provinces. The density of poultry farms in these regions were $2.2{\pm}1.1/km^2$ and $4.2{\pm}5.6/km^2$, respectively. In addition, reared animal numbers ranged between 6,537 and 24,250 individuals in poultry farms located in HPAI outbreak regions. Following identification of poultry farms in HPAI outbreak regions, an HPAI outbreak prediction model was designed using factors such as the habitat range for migratory birds(HMB), freshwater system characteristics, and local road networks. Using these factors, poultry farms which reared 6,500-25,000 individuals were filtered and compared with number of farms actually affected by HPAI outbreaks in the ROK. The HPAI prediction model shows that 90.0% of the number of poultry farms and 54.8% of the locations of poultry farms overlapped between an actual HPAI outbreak poultry farms reported in 2014 and poultry farms estimated by HPAI outbreak prediction model in the present study. These results clearly show that the HPAI outbreak prediction model is applicable for estimating HPAI outbreak regions in ROK.

Present Status of the Quality Assurance and Control (QA/QC) for Korean Macrozoobenthic Biological Data and Suggestions for its Improvement (해양저서동물의 정량적 자료에 대한 정도관리 현실과 개선안)

  • CHOI, JIN-WOO;KHIM, JONG SEONG;SONG, SUNG JOON;RYU, JONGSEONG;KWON, BONG-OH
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.26 no.3
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    • pp.263-276
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    • 2021
  • Marine benthic organisms have been used as the indicators for the environment assessment and recently considered as a very important component in the biodiversity and ecosystem restoration. In Korean waters, the quantitative data on marine benthos was used as one of major components for the marine pollution assessment for 50 years since 1970s. The species identification which is an important factor for the quantitative biological data was mainly performed by the marine benthic ecologists. This leads to the deterioration of the data quality on marine benthos from the misidentication of major taxonomic groups due to the lack of taxonomic expertise in Korea. This taxonomic problem has not been solved until now and remains in most data from national research projects on the marine ecosystems in Korean waters. Here we introduce the quality assurance and control (QA/QC) system for the marine biological data in UK, that is, NMBAQC (Northeast Atlantic Marine Biological Analytic and Quality Control) Scheme which has been performed by private companies to solve similar species identification problems in UK. This scheme asks for all marine laboratories which want to participate to any national monitoring programs in UK to keep their identification potency at high level by the internal quality assurance systems and provides a series of taxonomic workshops and literature to increase their capability. They also performs the external quality control for the marine laboratories by performing the Ring Test using standard specimens on various faunal groups. In the case of Korea, there are few taxonomic expertise in two existing national institutions and so they can't solve the taxonomic problems in marine benthic fauna data. We would like to provide a few necessary suggestions to solve the taxonomic problems in Korean marine biological data in short-terms and long-terms: (1) the identification of all dominant species in marine biological data should be confirmed by taxonomic expertise, (2) all the national research programs should include taxonomic experts, and (3) establishing a private company, like the Korea marine organism identification association (KMOIA), which can perform the QA/QC system on the marine organisms and support all Korean marine laboratories by providing taxonomic literature and species identification workshops to enhance their potency. The last suggestion needs more efforts and time for the establishment of that taxonomic company by gathering the detailed contents and related opinions from diverse stakeholders in Korea.