• Title/Summary/Keyword: effective modification method

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Label-free and sensitive detection of purine catabolites in complex solutions by surface-enhanced raman spectroscopy

  • Davaa-Ochir, Batmend;Ansah, Iris Baffour;Park, Sung Gyu;Kim, Dong-Ho
    • Journal of Surface Science and Engineering
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    • v.55 no.6
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    • pp.342-352
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    • 2022
  • Purine catabolite screening enables reliable diagnosis of certain diseases. In this regard, the development of a facile detection strategy with high sensitivity and selectivity is demanded for point-of-care applications. In this work, the simultaneous detection of uric acid (UA), xanthine (XA), and hypoxanthine (HX) was carried out as model purine catabolites by surface-enhanced Raman Spectroscopy (SERS). The detection assay was conducted by employing high-aspect ratio Au nanopillar substrates coupled with in-situ Au electrodeposition on the substrates. The additional modification of the Au nanopillar substrates via electrodeposition was found to be an effective method to encapsulate molecules in solution into nanogaps of growing Au films that increase metal-molecule contact and improve substrate's sensitivity and selectivity. In complex solutions, the approach facilitated ternary identification of UA, XA, and HX down to concentration limits of 4.33 𝜇M, 0.71 𝜇M, and 0.22 𝜇M, respectively, which are comparable to their existing levels in normal human physiology. These results demonstrate that the proposed platform is reliable for practical point-of-care analysis of biofluids where solution matrix effects greatly reduce selectivity and sensitivity for rapid on-site disease diagnosis.

Selective removal of cationic dye pollutants using coal ash-derived zeolite/zinc adsorbents

  • Chatchai Rodwihok;Mayulee Suwannakaew;Sang Woo Han;Siyu Chen;Duangmanee Wongratanaphisan;Han S. Kim
    • Membrane and Water Treatment
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    • v.14 no.3
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    • pp.121-128
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    • 2023
  • This study introduces a NaOH/Zn-assisted hydrothermal method for the synthesis of zeolites derived from coal ash (CA). A zeolite/Zn adsorbent is successfully prepared by the activation of CA with NaOH and Zn; it is characterized by a high surface area and a negative surface charge.Methylene blue (MB) and methyl orange (MO) are selected as dye pollutants, and their adsorption onto the zeolite/Zn adsorbent is investigated. Results show the high adsorption capacities of MB and MO and that the negative surface charge facilitates electrostatic interactions between the adsorbates and adsorbents. The zeolite/Zn adsorbents shows the selective adsorption of positively charged dye MB via electrostatic interactions between the =NH+ group (positive dipole) and the oxygen functional group of the adsorbents (negative dipole). The selectivity for the positively charged dye is sufficiently high, with the removal efficiency reaching 99.41% within 10 min. By contrast, the negatively charged dye MO exhibits negligible absorption. These findings confirm the role of electrostatic interactions in the adsorption of MB, in addition to the effect of a large surface area. The results of this study are expected to facilitate the development of simple, eco-friendly, and cost-effective zeolite-based adsorptive composites from CA residuals for the selective removal of dye pollutants from CA waste.

전략적 성과측정 및 평가시스템의 개발과 적용에 관한 연구

  • 이승규;라준영;이수열
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1998.10a
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    • pp.114-117
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    • 1998
  • Failure to link business or operations strategy with the activities of operations is a critical problem in strategy implementation process. This problem comes from malfunction of a coordination and control mechanism to support the strategic direction by effective communication throughout the firm. A performance measurement and evaluation system (PMES) is thought as a core mechanism to monitor, direct. and induce desirable activities. We have developed a new strategic PMES (SPMES) that can effectively support the manufacturing strategy by utilizing customized performance measures. They are selected from a pool of four distinct but closely related sets of performance measures; financial, market, internal competency, and performance driver. In this paper, we briefly review the structure of the SPMES and explain the change process of PMES into SPMES in manufacturing business units. First we analyze the business environment and manufacturing strategy to identify short- and long-term issues facing the management. Next step is scrutinizing the objectives and activities of every function and process in the business unit. Using the information obtained, we can diagnose the gaps between currently effective PMES and desirable SPMES supporting the strategies. Once the problems in existing system are identified, we reconfigure the existing and new measures to establish a SPMES through a series of analyses, discussions and workshops. In organizing the selected measures in the new system, we use AHP method to reflect the relative importance of the measures in a specific business. Finally, modification or development of information system to support the SPMES wraps up the development process, and implementation begins. We explain the entire process using two cases to clarify the real meanings and the difficulties of PMES change process.

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An Effective Path Table Method Exploiting the Region Numbering Technique (영역 할당 기법을 이용한 효율적인 경로 테이블 기법)

  • Min Jun-Ki
    • The KIPS Transactions:PartD
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    • v.13D no.2 s.105
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    • pp.157-164
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    • 2006
  • Since XML is emerging as the de facto standard for exchanging and representation of data on the web, the amount of XML data has rapidly increased. Thus, the need for effective store and retrieval of U data has arisen. Since the existing techniques such as XRel which is an XML storage and management technique using RDBMS simply record the existing all label paths, diverse classes of label path expressions could not be efficiently supported. In this paper, we present a technique which supports storage and retrieval for XML data using RDBMS efficiently compared with the existing approaches. Since the proposed technique keeps the XML path index on the relational database and replace label paths with path identifiers, diverse XML queries can be evaluated compared with existing approaches. Also, the proposed technique does not require the modification of the relational database engine and consumes the disk space less. Our experimental result demonstrates the better query performance compared with existing techniques.

Studies on Anti-cancerous Substances from Higher Plane in East Asian Region

  • Takeya, Koichi
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 1999.10a
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    • pp.1-45
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    • 1999
  • To date many kinds of compounds have been obtained from plants kingdom as antineoplastic and anti-cancerous agents. However, there is no special type of compounds for ncancer therapy. Various types of substances are effective for various types of cancers and tumors: for instance, alkaloids, lignans, terpenes and steroids etc. Curcumol obtained from Curcuma aromatica was tested and noticed to be effective against cancer of the uterine cervix clinically Oridonin isolated from Rabdosia ssp.is now investigated for clinical trials in China. Moreover, camptothecine isolated from Camptotheca acuminata is also antineoplastic alkaloid, but is very toxic. Chemical modification has been tried to decrease its toxicity. This compound is now using as clinical agent. Harringtonin was investigated as an anticancerous drug in China. Taxol, a compound with a taxane ring isolated from the bark of Taxus brevifolia, has been demonstrated to have substantial anticancer activity in patients with solid tumors refractory standard chemotherapy. Supply of this drug has severely limited full exploration of its antineoplastic potential. Some efforts are continued in National Cancer Institute NCI) Washington for surveying various Taxus species for optimal taxol content, improvement in semi-synthesis from baccatin III, improvement in method of extraction, and development of alternative renewable resources. Further, there are many compounds which have been reported as antineoplastic agents. On the other hand, we have screened on higher plants collected in Japan, China, Korea, Southeast Asia and South America for antineoplastic activity, which has been done using Sarcoma 180 ascites in mice, P388 Iymphocytic leukemia in mice, Chinese hamster lung V-79 cells, P388 cells and nasopharynx carcinoma (KB) cells in our laboratory, as primary screening. In this meeting, I will present on antitumor and cytotoxic substances of the higher plants (Rubia cordifolia, Ailanfhus Vilmoriniana, Aster tataricus, Taxus cuspidata var. nana, Cephalotaxus harringtonia var drupacea, etc.) selected from above screening tests.

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Studies on Anti-Cancerous Substances from Higher Plants in East Asian Region

  • Takeya, Koichi
    • Plant Resources
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    • v.3 no.1
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    • pp.1-45
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    • 2000
  • To date many kinds of compounds have been obtained from plants kingdom as antineoplastic and anti-cancerous agents. However, there is no special type of compounds for cancer therapy. Various types of substances are effective for various types of cancers and tumors: for instance, alkaloids. lignans, terpenes and steroids etc. Curcumol obtained from Curcuma aromatica was tested and noticed to be effective against cancer of the uterine cervix clinically. Oridonin isolated from Rabdosia ssp. is now investigate for clinical trials in China. Moreover camptothecine isolated from Camptotheca acuminata is also antineoplastic alkaloid, but is very toxic. Chemical modification has been tried to decrease its toxicity This compound is now using as clinical agent. Harringtonin was investigated as an anticancerous drug in China. Taxol, a compound with a taxane ring isolated from the bark of Taxus brevifotia. has been demonstrated to have substantial anticancer activity in patients with solid tumors refractory standard chemotherapy. Supply of this drug has severely limited full exploration of its antineoplastic potential Some efforts are continued in National Cancer Institute(NCI) Washington for surveying various Taxus species for optimal taxol content, improvement in semi-synthesis from baccatin 111, improvement in method of extraction, and development of alternative renewable resources. Further, there are many compounds which have been reported as antineoplastic agents. On the other hand, we have screened on higher plants collected In Japan, China, Korea. Southeast Asia and South America for antineoplastic activity, which has been done using Sarcoma 180 ascites in mice, P388 Iymphocytic leukemia In mice, Chinese hamster lung V-79 cells, P388 cells and nasopharynx carcinoma(KB) cells in our laboratory, as primary screening. In this meeting, 1 will present on antitumor and cytotoxic substances of the higher plants(Rubis cordifolia, Ailanthus vilmoriniana, Aster tataricus, Taxus cuspidata var. nana, Cephalotaxus harringtonia var. drupacea, etc.) selected from above screening tests.

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Effective address assignment method in hierarchical structure of Zigbee network (Zigbee 네트워크 계층 구조에서의 효율적인 주소 할당 방법)

  • Kim, Jae-Hyun;Hur, Soo-Jung;Kang, Won-Sek;Lee, Dong-Ha;Park, Yong-Wan
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.44 no.10
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    • pp.20-28
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    • 2007
  • Zigbee sensor network base on IEEE802.15.4 has local address of 2 byte on transmit packet data which is pick up the address for each sensor node. Sensor network is requested low power, low cost, many nodes at hues physical area. There for Zigbee is very good solution supporting for next Ubiquitous generation but the Zigbee sensor network has address allocation problem of each sensor node. Is established standard from Zigbee Alliance, to the address allocation method uses Cskip algorithm. The Cskip algorithm use the hazard which allocates an address must blow Hop of the maximum modification and child node number. There is to address allocation and from theoretically it will be able to compose a personal 65536 sensor nodes only actual with concept or space, only 500 degree will be able to compose expansion or the low Zigbee network. We proposed an address allocation method using coordinate value for Zigbee sensor network.

The TVOC management level evaluation of adhesive product following to simultaneous revision of indoor air quality testing methods and standards (실내공기질 공정시험방법과 기준의 동시 개정에 따른 접착제 제품의 TVOC 관리수준 평가)

  • Yoo, Ji-Ho;Park, Joon-Man;Kim, Man-Goo
    • Analytical Science and Technology
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    • v.23 no.3
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    • pp.255-260
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    • 2010
  • The Ministry of Environment simultaneously revised testing methods and emission standards of adhesives product on the "Law of indoor air quality management" for the effective management of the building materials releasing pollutants in great quantities. Accordingly, it is impossible to compare original standards with revised standards directly. The influences of each factor of the revised testing methods of adhesive product on the emission rate of pollutants are reviewed through comparing with the original testing method. Through this study, revised pollutant emission control standards were assessed. With the result that it is found that emission rate of adhesives product is weakened two and half times by changing test period and the emission rate resulting from changing drying time has little difference. As a result of comparing TVOC emission standards with the original testing method considering the modification of testing methods, it is found that the emission standard through this revision is strengthened about 2.1 times more than that of present testing method.

A Study on the Effective Algorithms for tine Generalization (선형성 지형자료의 일반화에 대한 효율적인 알고리즘에 관한 연구)

  • 김감래;이호남
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.12 no.1
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    • pp.43-52
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    • 1994
  • This paper outlines a new approach to the line generalization when preparing small scale map on the basis of existing large scale digital map. Line generalizations are conducted based on Douglas algorithm using 1/25,000 scale topographic maps of southeastern JEJU island which produced by National Geographic Institute to analyze the fitness to the original and problems of graphical representation. Compare to the same scale map which was generated by manual method, a verity of small, but sometimes significant errors & modification of topological relationship have been detected. The research gives full details of three algorithms that operationalize the smallest visible object method, together with some empirical results. A comparison of the results produced by the new algorithms with those produced by manual generalization and Douglas method of data reduction is provided. Also this paper presents the preliminary results of an relationships between the size of smallest visual object and requiring data storages for each algorithms.

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Emission Reduction of Air Pollutants Produced from Chemical Plants

  • Lee, Byeong-Kyu;Cho, Sung-Woong
    • Journal of Korean Society for Atmospheric Environment
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    • v.15 no.E
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    • pp.29-38
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    • 1999
  • This study identified emission sources and emissions of air pollutants such as volatile organic compounds (VOCs), solvents, and acid gases produced from chemical plants. We collected air samples from various processes, reactors and facilities using VOC detectors and workers' experience. We identified chemical structures and emission concentrations of air pollutants. We analyzed total emissions of air pollutants emitted from the chemical plants. Also, we developed some emission reduction technologies based on chemical types and emission situations of the identified air pollutants. For reduction of air emissions of acid gases, we employed a method improving solubility of pollutants by reducing scrubber operation temperature, increasing surface area for effective contact of gas and liquid, and modifying or changing chemicals used in the acid scrubbers. In order to reduce air emissions of both amines and acid gases, which have had different emission sources each other but treated by one scrubber, we first could separate gas components. And then different control techniques based on components of pollutants were applied to the emission sources. That is, we first applied condensation and then acid scrubbing method using H2SO4 solution for amine treatment. However, we only used an acid scrubbing method using H2O and NaOH solution for acid gas treatment. In order to reduce air emissions of solvents such as dimethylformamide and toluene, we applied condensation and activated carbon adsorption. In order to reduce air emissions of mixture gases containing acid gases and slovents, which could not be separated in the processes, we employed a combination of various air pollution control devices. That is, the mixture gases were passed into the first condenser, the acid scrubber, the second condenser, and the activated carbon adsorption tower in sequence. In addition, for improvement of condensation efficiency of VOCs, we changed the type of the condensers attached in the reactors as a control device modification. Finally, we could successfully reduce air emissions of pollutants produced from various chenmical processes or facilities by use of proper control methods according to the types and specific emission situations of pollutants.

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