• Title/Summary/Keyword: OFS

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Nanoporous Organo-functional Silica Synthesis Based on a Purely Inorganic Precursor

  • Oh, Chang-Sup;Koo, Kyung-Wan;Han, Chang-Suk;Kim, Jang-Woo;Kim, Heon-Chang;Lee, Yong-Sang;Choi, Young-Tai;Kim, Yong-Ha
    • Korean Journal of Metals and Materials
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    • v.47 no.8
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    • pp.516-521
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    • 2009
  • In this study we report a rapid synthesis of nanoporous organo-functional silica (OFS) with unimodal and bimodal pore structures encompassing pores ranging from meso-to macroscale. The problems of tediousness and high production cost in the conventional syntheses are overcome by co-condensation of an inexpensive inorganic precursor, sodium silicate with an organosilane containing trimethyl groups. The insitu covalent anchoring of the non-polar trimethyl groups to the inner pore walls prohibits irreversible shrinkage of the wet-gel during microwave drying at ambient pressure and thus larger size pores (from ca. 20 to ca. 100 nm) can be retained in the dried silica. The drying process of the silylated wet-gels at an ambient pressure can be greatly accelerated upon microwave exposure instead of drying in an oven or furnace. Using this approach, anoporous and superhydrophobic silicas showing a wide variation in texture and morphology can be readily synthesized in roughly two hours. The effects of various sol-gel parameters solely on the textural properties of the organo-functional silica (OFS) have been investigated and discussed.

Identification of a Copy Number Variation on Chromosome 20q13.12 Associated with Osteoporotic Fractures in the Korean Population

  • Park, Tae-Joon;Hwang, Mi Yeong;Moon, Sanghoon;Hwang, Joo-Yeon;Go, Min Jin;Kim, Bong-Jo
    • Genomics & Informatics
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    • v.14 no.4
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    • pp.216-221
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    • 2016
  • Osteoporotic fractures (OFs) are critical hard outcomes of osteoporosis and are characterized by decreased bone strength induced by low bone density and microarchitectural deterioration in bone tissue. Most OFs cause acute pain, hospitalization, immobilization, and slow recovery in patients and are associated with increased mortality. A variety of genetic studies have suggested associations of genetic variants with the risk of OF. Genome-wide association studies have reported various single-nucleotide polymorphisms and copy number variations (CNVs) in European and Asian populations. To identify CNV regions associated with OF risk, we conducted a genome-wide CNV study in a Korean population. We performed logistic regression analyses in 1,537 Korean subjects (299 OF cases and 1,238 healthy controls) and identified a total of 8 CNV regions significantly associated with OF (p < 0.05). Then, one CNV region located on chromosome 20q13.12 was selected for experimental validation. The selected CNV region was experimentally validated by quantitative polymerase chain reaction. The CNV region of chromosome 20q13.12 is positioned upstream of a family of long non-coding RNAs, LINC01260. Our findings could provide new information on the genetic factors associated with the risk of OF.

A Methodology for Monitoring Prestressed Force of Bridges Using OFS-embedded Strand (광섬유센서가 내장된 강연선을 이용한 교량의 장력 모니터링 방법)

  • Kim, Hyoun-Wo;Kim, Jae-Min;Kim, Jin-Won;Kim, Young-Sang;Yun, Chung-Bang
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2008.04a
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    • pp.133-138
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    • 2008
  • This study proposes a novel method for in-service evaluation of force in an external prestressing 7-wire tendon which is employed for retrofitting bridge superstructure. For this propose, a smart strand 7.0m long whose king wire is replaced by a steel tube and the FBG sensor, is developed. Performance of the strand is demonstrated through loading-unloading tests for a RC T-shaped beam 6.4m long. Finally, a couple of test results are presented to discuss effect of temperature change in the FBG sensor.

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Goal Setting in Multiple Criteria Decision Making

  • Lee, Jae-Kyu
    • Journal of the Korean Operations Research and Management Science Society
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    • v.11 no.2
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    • pp.51-68
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    • 1986
  • The effects of goal setting in the context of Multiple Criteria Making (MCDM) are classified into two types : internal and external. In the internal models, the impact of the changed goal is limited only to the other goals in MCDM model. By contrast, in the external models, the impact is limited to the factors not included in the MCDM model. In fact, most real world examples of goal setting have the nature of mixed models. To assist in the goal setting process, the framework named Goal Setting Support (GSS) is developed. The GSS helps decision-makers for mixed models to 1) make internal trade-offs in a way that guarantees non-dominancy after the trade-ofs, and 2) evaluate achieved goals systematically. The GSS can be used in creating Decision Support Systems that will allow interactive goal setting.

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Response of Yield and Nitrogen Use Efficiency for Garlic on Different Types and Rates of Organic Fertilizer (유기질 비료의 종류 및 시비량이 마늘의 수량과 질소이용효율에 미치는 영향)

  • Kim, Seong Heon;Hwang, Hyun Young;Seo, Hye Bin;Rim, Jae Eun;Park, Seong Jin;Lee, Yun Hae;Kim, Myung Sook
    • Journal of the Korea Organic Resources Recycling Association
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    • v.27 no.4
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    • pp.35-42
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    • 2019
  • Organic fertilization (OF) was an effective management strategy to improve crop yield and soil fertility. Determination of optimum application rate has been received great interest as a major research field. In this study, we evaluated optimum application level of three different organic fertilizers; mixed expeller compost (MEC), mixed organic fertilizer (MOF) and organic complex fertilizer (OCF), for garlic cultivation. Treatments consisted of MEC, MOF, OCF (50, 100, 150% of standard nitrogen input), inorganic fertilizer(NPK, N-P2O5-K2O : 250-78-128 kg ha-1) and no-fertilization (control). Overall, the yields of garlic under MEC, MOF and OCF 100% (5,337, 5,617 and 5,276 kg ha-1) were higher than under control (4,496 kg ha-1). The 100% of three OFs treatements showed the highest yield and bulb diameter, similar with NPK, while leaf length and bulb height were not significantly different among all treatments. The 150% of three OFs rather decreased yield. The highest nitrogen use efficiency (38.4 and 38.0%) was observed in MOF 100% and OCF100%, which was the most similar with that in NPK (38.8%). As OF application rate increased, pH was decreased, but soil NO3-N and NH4-N were increased. There was no significant difference in soil organic matter (OM), av. P2O5 and Ex. cation values. From these results, 100% application of OFs could be recommended as a suitable input level for garlic cultivation, regardless of organic fertilizer types. Further study might be required to evaluate long-term OF application effect on soil health and crop productivity.

A Fluidity Experiment of Pre-Mix Cement for Dispersibility Improvement of Mineral Admixture (광물질 혼화재의 분산성 향상을 위한 프리믹스 시멘트의 유동성 실험)

  • Han, Cheon-Goo;Lee, Hai-Ill;Noh, Sang-Kyun;Kim, Ki-Hoon
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.4 no.2
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    • pp.90-96
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    • 2009
  • The high rising building construction makes increasing the requirement of high strength concrete. Especially, the workability analysis is related with dispersion of admixture such as SF for improving strength and FA, BS for reducing construction cost and improving durability of Ultra High Strength Concrete which has over 100 MPa of compressive strength is very important. Precisely, decreases dispersion because of lumping situation of each admixture and it causes the workability of admixture is decreased. Therefore, the workability of cement paste is tested for analyze effects of pre-mixed cement for solving those problems with it to this research. The summary of the results are like below. First of all, OBS is increasing workability more than OFS. This result causes that the glassy surface of BS in the OBS is increasing workability and the absorption of admixture of FA in the OFS is decreasing workability. In the case of mixing methods, pre-mixing method is increasing workability more than normal one. This result shows that the normal mixing method is bad dispersion of binders. The other side, the pre-mixing method is good. Furthermore, depending on the mixing time, according to the increasing mixing time such as 30, 60, and 120 seconds, the dispersion of binders and workability turns better.

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A Study on Vocational Rehabilitation Evaluation Tool for Mental Disorders (정신장애인 직업재활 평가도구에 대한 고찰)

  • Jeong, Eun-Hwa
    • Therapeutic Science for Rehabilitation
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    • v.11 no.4
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    • pp.41-53
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    • 2022
  • Objective : The purpose of this study is to identify and analyze the vocational rehabilitation evaluation tool for the mentally disabled. Methods : For literature search, the Pubmed database was used, and for the analysis, the development year, evaluation method, number of items, scale, and evaluation items were analyzed. In the analysis method, each evaluation item was divided into four categories: function, internal factor, environment, and mental symptom, and the evaluation elements of each evaluation tool were identified. Results : When searching Pubmed through search terms, 161 documents were retrieved. According to the selection method, Griffiths Work Behavior Scale (GWBS), Occupational Functioning Scale (OFS), Social and Occupational Functioning Assessment Scale (SOFAS), Work Ability Index (WAI), Work Behavior Inventory (WBI), Work Environment Impact Scale (WEIS), and Work and Social Adjustment Scale (WSAS) were screened. The evaluation items of all evaluation tools included job-related functional evaluation. According to the purpose of each evaluation tool, internal factors, environment, and mental symptoms were measured. Conclusion : Occupational skills are skills in which various functions such as physical, cognitive, social skills, and coping skills act in a complex way. Therefore, it is necessary to include the four factors analyzed in this study: function, internal factors, environment, and psychiatric symptoms.

Late Pleistocene Fluvial Sequence in South Korea

  • Kim, Ju-Yong;Yang, Dong-Yoon;Nahm, Wook-Hyun;Lee, Yung-Jo;Park, Ji-Hoon
    • The Korean Journal of Quaternary Research
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    • v.18 no.2 s.23
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    • pp.33-42
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    • 2004
  • In South Korea a Pedo-sedimentary Sequence(PS) indicating the Last Glacial Maximun(LGM) is typified y a brown to dark brown, relatively stiff paleosol layers formed by repetitive freezing and thawing processes which in turn left characteristi glossic textures in soil-solum, polygolnal structures with a flagipans, vertical soil wedges or freezing cracks, and horizontal foliations, As a pre-LGM sedimentary sequences (older than 25Ka), the Old Fluvial Sequence(OFS) overlain by the Slope Sedimentary Sequence(SS) are distributed commonly at the base level higher than 14-15m above present river-bed along the major river basin. After the LGM (ca. 18Ka), the Young Fluvial Sequence(YFS) appears at an altitude ascending order of sedimentary profiles. In this fluvial organic muds of Jangheungri site(Jinju), Sorori site(Cheonwon), and Youngsan estruarine rivermouth(Mokpo) were exemplified in order to interpret their formation ages and environments. As result of $^{14}C$ datings, the formation ages of te organic muds are Boelling to Alleroed (MIS-1). These organic muds were fomed in fluvial backswamp or local pond/bog in response to shifting fluvial system. On the basis of palynological production dominant with Abies/Picea-Betula and Ranunculaceae, Compositae, Cyperaceae, and Graminae, it was interpreted that more boreal to subboreal condition was prevailed rather than temperate like today during the formation of organic muds and soil moisture condition was a repetition of wet and dry condition.

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A Methodology for Monitoring Prestressed Force of Bridges Using OFS-embedded Stand (광섬유센서가 내장된 강연선을 이용한 교량의 장력 모니터링 방법)

  • Kim, Jae-Min;Kim, Hyun-Woo;Kim, Young-Sang;Kim, Jin-Won;Yun, Chung-Bang
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.21 no.3
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    • pp.287-294
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    • 2008
  • This study proposes a novel method for in service evaluation of tension force of a prestressed 7-wire strand which is frequently employed for retrofitting bridge superstructure. The smart strand is made by replacing the straight king wire of the strand with an instrumented steel tube in which the FBG sensor is embedded. Since the strain of the smart strand can easily be measured using the sensor, it is possible to monitor tension force of the strand during the service. For the sake of demonstrating effectiveness of the proposed strand, we came up with a 7.0m long prototype with 2 FBG sensors, and it is applied as an external tendon to a 6.4m long and 0.6 high RC T-shaped beam. A loading-unloading test has been carried out, and estimated tension forces using the smart strand are compared with measured forces by load cell. The comparison showed that the proposed smart tendon is useful and accurate for monitering tension force of the prestressed tendon.