• Title/Summary/Keyword: Selective maintenance

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A Study on NOx Removal Efficiency using SNCR Process in the Industrial Waste Incineration Plant (산업폐기물 소각로에서 SNCR공정에 의한 NOx 제거효율에 관한 연구)

  • Ryu Hae-Yeol;Kim Min-Choul;Jung Jong-Hyeon;Lee Gang-Woo;Chung Jin-Do
    • Journal of Environmental Health Sciences
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    • v.31 no.4 s.85
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    • pp.332-339
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    • 2005
  • The environmental regulations in the world has been reinforced and many nations has devoted themselves to the development of cost-effective technology. Selective catalyst reduction(SCR) and selective non-catalyst reduction (SNCR) processes are mainly used to treat nitrogen oxidants generated from fossil-fuel combustion. One of these typical technologies for reduction of do-NOx is SNCR process has increased continuously because of the low cost for building and maintenance. Nevertheless the researches on the application to real scale plant by the reductant like Urea are rarely studied. In this paper, an experimental investigations were performed on the SNCR process in the industrial waste incineration plant. With no reducing agent, the concentration of NOx stayed in around 180 ppm $(O_2\;12\%)$ with the exhausting temperature of $950^{\circ}C$ and changed within the range of 20 ppm to remain relatively consistent. When $10\;wt\%)$ of a solution was added, the efficiency of denitrification reached above $61.4\%$ with the NSR of 2.0 and the exhausting temperature of $950^{\circ}C.$ When the concentration of the urea solution was set to $10\;wt\%$ and the sprinkling to four nozzles, the reaction temperature was reduced to about $50~100^{\circ}C$ with a mixture of $10\;wt\%\;CH_3OH\;and\;5wt\%\;Na_2CO_3$ in $40\;wt\%$ of the solution. The NOx removal efficiency increased to $78.4\%,$ achieving a broader and expansive range of reaction temperatures than the addition of an unmixed pure solution.

Selective Cache Consistency Maintenance Schemes Considering the Connection States in Mobile Computing Environments (이동 컴퓨팅 환경에서 접속 상태를 고려한 선택적 캐쉬 일관성 유지 기법)

  • Kim, Hee-Sook;Hwang, Byung-Yeon
    • Proceedings of the Korea Information Processing Society Conference
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    • 2003.05b
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    • pp.779-782
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    • 2003
  • 이동 컴퓨팅 환경에서 이동 호스트가 사용하는 캐쉬는 이동 호스트의 자치성을 증대시킴으로서 전력의 한계와 제한된 대역폭이라는 단점을 보완할 수 있는 중요한 장치로 사용된다. 하지만 서버 데이터와의 일관성 유지를 해야하는 부담을 가지게 된다. 본 연구에서는 기존의 일관성 유지 기법이 가지는 불필요한 데이터의 방송 문제점을 보완하고 오랜 접속 단절 후에 연결된 이동 호스트에 대해서는 서버가 보관하고 있던 지난 방송 정보를 전달함으로서 대역폭을 효율적으로 이용하면서 이동 호스트의 자치성을 증대시키는 캐쉬 유지 기법을 제안한다.

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Current Technologies and Related Issues for Mushroom Transformation

  • Kim, Sinil;Ha, Byeong-Suk;Ro, Hyeon-Su
    • Mycobiology
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    • v.43 no.1
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    • pp.1-8
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    • 2015
  • Mushroom transformation requires a series of experimental steps, including generation of host strains with a desirable selective marker, design of vector DNA, removal of host cell wall, introduction of foreign DNA across the cell membrane, and integration into host genomic DNA or maintenance of an autonomous vector DNA inside the host cell. This review introduces limitations and obstacles related to transformation technologies along with possible solutions. Current methods for cell wall removal and cell membrane permeabilization are summarized together with details of two popular technologies, Agrobacterium tumefaciens-mediated transformation and restriction enzyme-mediated integration.

A Molecular Approach to Mitophagy and Mitochondrial Dynamics

  • Yoo, Seung-Min;Jung, Yong-Keun
    • Molecules and Cells
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    • v.41 no.1
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    • pp.18-26
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    • 2018
  • Mitochondrial quality control systems are essential for the maintenance of functional mitochondria. At the organelle level, they include mitochondrial biogenesis, fusion and fission, to compensate for mitochondrial function, and mitophagy, for degrading damaged mitochondria. Specifically, in mitophagy, the target mitochondria are recognized by the autophagosomes and delivered to the lysosome for degradation. In this review, we describe the mechanisms of mitophagy and the factors that play an important role in this process. In particular, we focus on the roles of mitophagy adapters and receptors in the recognition of damaged mitochondria by autophagosomes. In addition, we also address a functional association of mitophagy with mitochondrial dynamics through the interaction of mitophagy adaptor and receptor proteins with mitochondrial fusion and fission proteins.

Enhancing Gas Response Characteristics of Mixed Metal Oxide Gas Sensors

  • Balamurugan, Chandran;Song, Sun-Ju;Kim, Ho-Sung
    • Journal of the Korean Ceramic Society
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    • v.55 no.1
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    • pp.1-20
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    • 2018
  • Semiconducting nanomaterials have attracted considerable interest in recent years due to their high sensitivity, selectivity, and fast response time. In addition, for portable applications, they have low power consumption, lightweight, simple in operation, a low maintenance cost. Furthermore, it is easy to manufacture microelectronic sensor structures with metallic oxide sensitive thin layers. The use of semiconducting metal oxides to develop highly sensitive chemiresistive sensing systems remains an important scientific challenge in the field of gas sensing. According to the sensing mechanisms of gas sensors, the overall sensor conductance is determined by surface reactions and the charge transfer processes between the adsorbed species and the sensing material. The primary goal of the present study is to explore the possibility of using semiconducting mixed metal oxide nanostructure as a potential sensor material for selective gases.

RNA Metabolism in T Lymphocytes

  • Jin Ouk Choi;Jeong Hyeon Ham;Soo Seok Hwang
    • IMMUNE NETWORK
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    • v.22 no.5
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    • pp.39.1-39.18
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    • 2022
  • RNA metabolism plays a central role in regulating of T cell-mediated immunity. RNA processing, modifications, and regulations of RNA decay influence the tight and rapid regulation of gene expression during T cell phase transition. Thymic selection, quiescence maintenance, activation, differentiation, and effector functions of T cells are dependent on selective RNA modulations. Recent technical improvements have unveiled the complex crosstalk between RNAs and T cells. Moreover, resting T cells contain large amounts of untranslated mRNAs, implying that the regulation of RNA metabolism might be a key step in controlling gene expression. Considering the immunological significance of T cells for disease treatment, an understanding of RNA metabolism in T cells could provide new directions in harnessing T cells for therapeutic implications.

A multi-user selective undo/redo approach for collaborative CAD systems

  • Cheng, Yuan;He, Fazhi;Xu, Bin;Han, Soonhung;Cai, Xiantao;Chen, Yilin
    • Journal of Computational Design and Engineering
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    • v.1 no.2
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    • pp.103-115
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    • 2014
  • The engineering design process is a creative process, and the designers must repeatedly apply Undo/Redo operations to modify CAD models to explore new solutions. Undo/Redo has become one of most important functions in interactive graphics and CAD systems. Undo/Redo in a collaborative CAD system is also very helpful for collaborative awareness among a group of cooperative designers to eliminate misunderstanding and to recover from design error. However, Undo/Redo in a collaborative CAD system is much more complicated. This is because a single erroneous operation is propagated to other remote sites, and operations are interleaved at different sites. This paper presents a multi-user selective Undo/Redo approach in full distributed collaborative CAD systems. We use site ID and State Vectors to locate the Undo/Redo target at each site. By analyzing the composition of the complex CAD model, a tree-like structure called Feature Combination Hierarchy is presented to describe the decomposition of a CAD model. Based on this structure, the dependency relationship among features is clarified. B-Rep re-evaluation is simplified with the assistance of the Feature Combination Hierarchy. It can be proven that the proposed Undo/Redo approach satisfies the intention preservation and consistency maintenance correctness criteria for collaborative systems.

Energy-Efficient Routing Protocol for Hybrid Ad Hoc Networks (하이브리드 애드 혹 네트워크에서의 에너지 효율성을 고려한 라우팅 알고리즘)

  • Park, Hye-Mee;Park, Kwang-Jin;Choo, Hyun-Seung
    • Journal of Internet Computing and Services
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    • v.8 no.5
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    • pp.133-140
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    • 2007
  • Currently, as the requirement for high quality Internet access from anywhere at anytime is consistently increasing, the interconnection of pure ad hoc networks to fixed IP networks becomes increasingly important. Such integrated network, referred to as hybrid ad hoc networks, can be extended to many applications, including Sensor Networks, Home Networks, Telematics, and so on. We focus on some data communication problems of hybrid ad hoc networks, such as broadcasting and routing. In particular. power failure of mobile terminals is the most important factor since it affects the overall network lifetime. We propose an energy-efficient routing protocol based on clustering for hybrid ad hoc networks. By applying the index-based data broadcasting and selective tuning methods, the infra system performs the major operations related to clustering and routing on behalf of ad hoc nodes. The proposed scheme reduces power consumption as well as the cost of path discovery and maintenance, and the delay required to configure the route.

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Effect of Selective Consumption on Intake, Diet Selectivity and Passage Kinetics of Wheat Straw by Barbari Goats

  • Biswal, B.;Hasan, Q.Z.;Sharma, K.;Dutta, N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.7
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    • pp.913-917
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    • 2000
  • Sixteen adult Barbari bucks were divided into 4 homogeneous groups, each group was offered wheat straw (WS) at levels 75, 100, 125 and 150 per cent of ad libitum intake in a factorial randomized complete block design. All goats were uniformly fed a supplement ($13.5g\;DM/kg\;W^{0.75}$) to fulfill their requirement for protein at maintenance level. The experimental feeding of goats at different levels for 21 days was followed by a digestion trial of 6 days and determination of rate of passage of digesta for 144 h duration, respectively. Intake ($g/kg\;W^{0.75}$) of dry matter (DM), organic matter (OM), digestible DM and digestible OM increased with increase in amount of WS offered. The levels of WS refusals for obtaining upper limit of intake was found to be above 30% of DMO. Concentration of ADF and lignin was significantly lower and CP was higher (p>0.05) in food ingested relative to food offered or refused in response to increasing allowance of WS. Dietary means of particulate rate of passage from rumen, transit time and total mean retention time ranged from 0.032 to 0.036/h, 19.10 to 21.72/h and 58.61 to 61.53/h respectively and did not show significant differences (p>0.05) irrespective of dietary level of WS. The results suggest that DMI and quality of ingested WS would improve with higher rates of offer and refusals (${\geq}30%$ of DMO) without any pronounced effect on passage kinetics of digesta, because of the greater opportunity afforded to goats for selective feeding.

Influence of Panax ginseng formulation on skin microbiota: A randomized, split face comparative clinical study

  • Hou, Joon Hyuk;Shin, Hyunjung;Shin, Hyeji;Kil, Yechan;Yang, Da Hye;Park, Mi Kyeong;Lee, Wonhee;Seong, Jun Yeup;Lee, Seung Ho;Cho, Hye Sun;Yuk, Soon Hong;Lee, Ki Yong
    • Journal of Ginseng Research
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    • v.46 no.2
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    • pp.296-303
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    • 2022
  • Background: Skin microbiota is important for maintenance of skin homeostasis; however, its disturbance may cause an increase in pathogenic microorganisms. Therefore, we aimed to develop a red ginseng formulation that can selectively promote beneficial bacteria. Methods: The effects of red ginseng formulation on microorganism growth were analyzed by comparing the growth rates of Staphylococcus aureus, S. epidermidis, and Cutibacterium acnes. Various preservatives mixed with red ginseng formulation were evaluated to determine the ideal composition for selective growth promotion of S. epidermidis. Red ginseng formulation with selected preservative was loaded into a biocompatible polymer mixture and applied to the faces of 20 female subjects in the clinical trial to observe changes in the skin microbiome. Results: Red ginseng formulation promoted the growth of S. aureus and S. epidermidis compared to fructooligosaccharide. When 1,2-hexanediol was applied with red ginseng formulation, only S. epidermidis showed selective growth. The analysis of the release rates of ginsenoside-Rg1 and -Re revealed that the exact content of Pluronic F-127 was around 11%. The application of hydrogel resulted in a decrease in C. acnes in all subjects. In subjects with low levels of S. epidermidis, the distribution of S. epidermidis was significantly increased with the application of hydrogel formulation and total microbial species of subjects decreased by 50% during the clinical trial. Conclusion: We confirmed that red ginseng formulation with 1,2-hexanediol can help maintain skin homeostasis through improvement of skin microbiome.