• Title/Summary/Keyword: 5'-Modification

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Oxygen and Hydrogen Isotopic Compositions of the Hwacheon Granite (화천화강암의 산소와 수소 동위원소 조성)

  • Park Young-Rok;Ko Bokyun
    • The Journal of the Petrological Society of Korea
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    • v.13 no.4
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    • pp.214-223
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    • 2004
  • Oxygen and hydrogen isotopic compositions of the Jurassic peraluminous Hwacheon granite were measured, and compared with those of other Jurassic peraluminous Daebo granite in Korea. $\delta$$\^$18/O values for quartz and feldspar of the Hwacheon granite range from 8.2 to 10.6 and 5.8 to 9.0$\textperthousand$, respectively. Whole rock $\delta$$\^$18/O values for banded biotite gneiss country rocks surrounding the Hwacheon granites range from 8.1 to 9.4$\textperthousand$. Whole rock and biotite $\delta$D Values for Hwacheon granite range from -84 to -113 and -107 to -113$\textperthousand$, respectively. Whole rock $\delta$D values for banded biotite gneiss country rocks range from -76 to -100$\textperthousand$. Both $\delta$$\^$18/O and $\delta$D values of the Hwacheon granite are characterized by low values compared to the 'normal' values for the fresh peraluminous granitic rocks. Low $\delta$$\^$18/O values of the Hwacheon granite resulted from fluid-rock interaction for a long period. Isotopic modelling result renders that a relatively low-$\delta$$\^$18/O fluid below -1$\textperthousand$ was involved in subsolidus isotopic exchange under a relatively high fluid/rock ratio (<-6). The fluid of meteoric origin has experienced a modification of oxygen isotopic composition as a result of fluid-rock interaction with the Hwacheon granite and surrounding metapelitic country rocks.

Preparation and Properties of Aminated Poly(ethersulfone) Ion-Exchange Membrane by UV Irradiation Method (UV 조사에 의한 아민화 Poly(ethersulfone) 이온교환막의 제조 및 특성)

  • Choi, Kuk-Jong;Hwan, Eui-Hwan;Rhee, Young-Woo;Hwang, Taek-Sung
    • Polymer(Korea)
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    • v.32 no.1
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    • pp.70-76
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    • 2008
  • The PES-g-BTCA membrane was synthesized by UV irradiation method and then used to be modified into the PES anion exchange membrane by the amination reaction. Their chemical structures and adsorption properties were investigated. The degree of grafting and amination were increased with increasing the reaction time and had the maximum values of 138% and 1.20 mmol/g at 80 min, respectively. The initial thermal degradation temperature of PES membrane was $400^{\circ}C$. Which was reduced as the surface modification reaction had proceeded. The values of contact angle for PES membrane were decreased from 68.1 to $40.2^{\circ}$ with increasing the extent of amination, the water up-take and ion exchange capacity were also increased with increasing UV irradiation time until 80 min. The average pore size and BET surface area were decreased in order of PES, PES-g-BTCA, and aminated PES ion exchange membrane. Their average pore sizes were 624.8, 359.7, and 138.5 ${\AA}$, and their surface areas were 10.1,9.7 and 1.7 $m^2/g$, respectively.

Antioxidant Property of Aqua-Acupuncture Solution from Circium japonicum (대계 약침액의 항산화 효능)

  • Lee, Jeong-Joo;Moon, Jin-Young
    • Korean Journal of Acupuncture
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    • v.22 no.4
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    • pp.57-65
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    • 2005
  • Objectives : Circium japonicum is a pharmacologically active used in traditional Korean medicine. An aqua-acupuncture solution of the Circium japonicum was assessed to determine the mechanism of its antioxidant activity. Materials : Circium japonicum was obtained from a Dongguk Korean Medicine Hospital (Kyung-ju, Kyungbuk). The freeze-dry powder was collected (yield 5.1%) for the aqua-acupuncture solution. Scavenging activity on DPPH free radicals by the Circium japonicum aqua-acupuncture solution (CJAS) was assessed according to the method followed by Gyamfi et al.. and then scavenging activity orl superoxide radicals $(O_2^-{\cdot})$ was assessed by the method described by Gotoh et al. with slight modification. Deoxyribose assay to determine the rate constant for the reactions between either antioxidants and hydroxyl radicals or antioxidants and iron ions. We tested by; (1) Non-site-specific scavenging assay (hydroxyl radicals, OH), (2) Site-specific scavenging assay (chelate iron ions), and (3) Pro-oxidant effect of the CJAS on iron dependent hydroxyl radical generation. Finally, we determined hydroxyl radical-mediated DNA nicking formation. Conclusion : Our study demonstrated that CJAS has antioxidant activities and we investigated the potential effectiveness of CJAS in preventing oxidative stress-mediated disease further.

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Surface Modification of Li Metal Electrode with PDMS/GO Composite Thin Film: Controlled Growth of Li Layer and Improved Performance of Lithium Metal Battery (LMB) (PDMS/GO 복합체 박막의 리튬 금속 표면 개질: 리튬전극의 성장 제어 및 리튬금속전지(LMB) 성능 향상)

  • Lee, Sanghyun;Seok, Dohyeong;Jeong, Yohan;Sohn, Hiesang
    • Membrane Journal
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    • v.30 no.1
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    • pp.38-45
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    • 2020
  • Although Lithium metal battery (LMB) has a very large theoretical capacity, it has a critical problem such as formation of dendrite which causes short circuit and short cycle life of the LMB. In this study, PDMS/GO composite with evenly dispersed graphene oxide (GO) nanosheets in poly (dimethylsiloxane) (PDMS) was synthesized and coated into a thin film, resulting in the effect that can physically suppress the formation of dendrite. However, PDMS has low ion conductivity, so that we attained improved ion conductivity of PDMS/GO thin film by etching technic using 5wt% hydrofluoric acid (HF), to facilitate the movement of lithium (Li) ions by forming the channel of Li ions. The morphology of the PDMS/GO thin film was observed to confirm using SEM. When the PDMS/GO thin film was utilized to lithium metal battery system, the columbic efficiency was maintained at 87.4% on average until the 100th cycles. In addition, voltage profiles indicated reduced overpotential in comparison to the electrode without thin film.

Sensor Fusion of Localization using Unscented Kalman Filter (Unscented Kalman filter를 이용한 위치측정 센서융합)

  • Lee, Jun-Ha;Jung, Kyung-Hoon;Kim, Jung-Min;Kim, Sung-Shin
    • Journal of the Korean Institute of Intelligent Systems
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    • v.21 no.5
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    • pp.667-672
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    • 2011
  • This paper presents to study the sensor fusion of positioning sensors using UKF(unscented Kalman filter) for positioning accuracy improvement of AGV(automatic guided vehicle). The major guidance systems for AGV are wired guidance and magnetic guidance system. Because they have high accuracy and fast response time, they are used in most of the FMS(flexible manufacturing system). However, they had weaknesses that are high maintenance cost and difficult of existing path modification. they are being changed to the laser navigation in recent years because of those problems. The laser navigation is global positioning sensor using reflecters on the wall, and it have high accuracy and easy to modify the path. However, its response time is slow and it is influenced easily by disturbance. In this paper, we propose the sensor fusion method of the laser navigation and local sensors using UKF. The proposed method is improvement method of accuracy through error analysis of sensors. For experiments, we used the axle-driven forklift AGV and compared the positioning results of the proposed method with positioning results of the laser navigation. In experimental result, we verified that the proposed method can improve positioning accuracy about 16%.

A reappraisal of the Acer wilsonii complex and Related Species in China (중국 Acer wilsonii 와 근연분류군의 분류학적 재검토)

  • Eom, Hyun Joo;de Jong, Piet C.;Chang, Chin-Sung
    • Korean Journal of Plant Taxonomy
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    • v.41 no.4
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    • pp.329-337
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    • 2011
  • The Acer wilsonii complex including A. wilsonii, A. tutcheri, and A. confertifoilum is distributed in southern China. Morphological variation was examined to delimit the species and to determine whether recognition at the specific level was warranted. Univariate and bivariate statistical methods, based on data taken from herbarium specimens, were used to examine morphological variation between and within species. This study showed that A. tutcheri differed from A. wilsonii by its rather short inflorescence, small leaf blades, and three leaf lobes with distinctive serrate leaf lobes. In contrast, there was virtually no separation of taxa with respect to the paniculate-corymbose or short paniculate inflorescence between A. confertifolium and A. tutcheri, suggesting that A. confertifolium morphologically resembled A. tutcheri and is a rather smaller form of it. Circumscription of Acer wilsonii has been quite troublesome, because the important holotype and isotype specimens contained different species under the same number and were misleading with respect to the correct application of the name. Furthermore, lobation is very weak within ser. Sinensia, but diversified inflorescences usually occur in China. A three lobed leaves species, A. wilsonii, represents the reduction in lobation without any modification of panicle inflorescences and seems to be closely related to A. sinense. However, A. tutcheri, which shows a reduction in panicle inflorescence with four petals and sepals, may not be closely related to A. sinense. Three lobed taxa may not correctly reflect the true relationship within ser. Sinensia. The designated lectotype of A. wilsonii, line drawings of representative leaves of related species, a key, and distribution maps of these taxa are presented.

A Study on the Compression of Construction Period by the Improvement of Trench Excavation for Slurry Wall Method (지하연속벽 시공 시 트렌치 굴착방법 개선을 통한 공기단축에 관한 연구: 현장적용사례를 중심으로)

  • Lee, Young Soo;Park, Hyung-Keun;Kang, Kyubyung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.5D
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    • pp.499-505
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    • 2012
  • As the excavation depths during excavation works in urban sites are getting deeper and bigger, It is necessary to study for the improvements to solve the problems in the excavation processes. This research deals with the excavation method that can not only minimize the effect on the surrounding constructions, but also shorten the construction period of the excavation work. For this research, there have been an extensive literature review of the bibliographic data about Slurry Wall Method, which is recognized around the world, and the analysis of the major problems in the existing ineffective construction step. These efforts led to the technical improvements. Accordingly, a new construction method applied with the new technical factors has been suggested, and it was possible to compare Slurry Wall Method with the construction method and analyze them on the base of the examples using the suggested method. This new method decreased the excavation period by 15 days. It took only 33days to finish the excavation work, as compared to 48 days that can be seen on the pre-modification schedule. Furthermore, the suggested method in this research is safer, more economically feasible, and better for the environment than Slurry Wall Method. It will contribute to shortening the construction period of Slurry Wall Method in the end.

Development of a Model of a Day Care Center for Rural Elderly People (농촌형 노인 주간보호시설 모형개발)

  • Kang, Kyung-Sook
    • Research in Community and Public Health Nursing
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    • v.15 no.4
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    • pp.551-565
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    • 2004
  • Purpose: The purpose of this study is to develop a day care center model focused on public health institutions for the elderly residing in their homes. Method: Research design for this study was a mult-level research, which consisted of a related literature review, an Internet search for knowledge of the current situation at home and abroad, on-site interviews, questionnaires collected from a sample of residents in a rural area, and a key-informants approach. Results: 1) The subjects of service - Generalized service should be provided to the elderly, 65 years and older, regardless of their assets. 2) The contents of service - Providing pre-health oriented and post-social welfare service that can integrate and satisfy a wide variety of public health and welfare needs of the elderly would strengthen the health care service of a day care center for the elderly. 3) Delivery system - Basic-level local self-governments should become a central operating body, and establishing a properly adjusted delivery system to a rural area after considering the efficiency and the access of vulnerable rural areas is needed based on modification of 'a Special Law for Agricultural and Fishery Areas' (rural public health center>rural health sub-center ${\rightarrow}$ unified health sub-center ${\rightarrow}$ public health hospital (public health center) ${\rightarrow}$ public welfare office). 4) Facility - Public health facilities such as public health centers and sub-centers should be located in areas that can easily access the facilities. 5) Funding - For day care center for the elderly in local self-government, the central government should modify a relevant implementation of subsidy in and provide some facilities and service regardless of the degree of self reliance of local self-government. 6) Human resources - It is needed to guarantee the period of workers of a day care center for the elderly, at least 3 to 5 years, with considering their specialty on aged care and avoiding circulation based positions. Furthermore, appropriate specially trained personnel such as medical workers and social workers should be placed to take care of both health service and welfare through strengthening of 'rules of law of elderly welfare,' Conclusion: future research is needed to test the model through a demonstration study using a model which may be developed in the future and to standardize the appraisal criteria of people hoping to enter a day care center for the elderly.

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Prognosis of Recurred TMD Patients According to Conservative Therapy (측두하악장애 재발환자의 보존적 처치에 따른 예후)

  • Ko, Myung-Yun;Kim, Ik-Hwan;Ok, Seung-Joon;Ahn, Yong-Woo
    • Journal of Oral Medicine and Pain
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    • v.32 no.2
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    • pp.241-250
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    • 2007
  • We examined 104 patients(primary group, controlled group) who had visited PNUH from 1994 to 2002, having been diagnosed as temporomandibular disorders(TMDs) and treated in conservative ways such as Behavior modification, medications, physical therapies and splint therapies. We also examined 54 patients(recurred group, experimental group) who had visited PNUH from 1991 to 2001, having been diagnosed as TMDs and experienced recurrence after conservatively treated. To find out the symptoms of Recurred TMD patients and their results of conservative treatments, we compared these two groups mentioned above. The obtained results were as follows: 1. Both primary and recurred groups have showed great improvements with conservative treatments. 2. Both primary and recurred groups have showed no differences in pain, LOM, MCO in their first visits but the noise were louder in primary group. 3. Both primary and recurred groups have showed no differences in pain, LOM, MCO when the treatments were over but the noise were louder in recurred group. 4. Treatments modalities, diagnosis, sex, kind of disease had not affected the results of treatment in either of groups. 5. It has come out that much better results were achieved when the patients in primary group had treated for over 6 months and for more than 10 times.

Prevalence and associated Factors of Metabolic Syndrome in a Rural Community (일부 농촌지역 주민들의 대사증후군 유병실태 및 관련요인)

  • Jo, Yeon Soon;Kwak, Joung Ok;Kim, Young Sin;Park, Seo Young;Seong, Yeon Hee;Woo, Do Im;Lee, Kyeong Ok;Lee, Mi Suk;Lee, Jung Kyung;Jo, Hyeon Ju;Choi, Jeong Hui;Han, Jung Ae;Kim, Bongjeong
    • Journal of Korean Academy of Rural Health Nursing
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    • v.7 no.1
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    • pp.5-17
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    • 2012
  • Purpose: The objectives of this study were to investigate the prevalence of the metabolic syndrome (MetS) and to identify associated factors with MetS among rural residents. Methods: Data were collected from 1,196 subjects over aged 30 years by a self-administered questionnaire, physical measurement, and blood test in a rural area. The prevalence of MetS was determined by the criteria of the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) and 2005 the Korean society for the study of obesity. Results: The prevalence of MetS was 40.5% for men, 49.2% for women. The prevalence of risk factors of MetS was 57.4% for elevated blood pressure, 49.0% for low HDL-cholesterol, and 48.6% for abdominal obesity. Unemployment and higher Body mass index (BMI) were associated factors for MetS regardless of gender. And higher age and physical inactivity in women only increased the odds of the MetS. Especially, BMI was a strong risk factor of MetS in both men and women. Conclusion: The prevalence of metabolic syndrome was higher in a rural area. Therefore, health care providers should develop lifestyle modification program to increase physical activity level and to prevent the obesity among rural residents in order to decrease the prevalence of MetS.