• Title/Summary/Keyword: PAO

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Development of Electric Power Management System for Electric Furnace (전기로 전력관리 시스템 개발)

  • Min, Byeong-Yong;Kim, Ho-Jin;Kwon, Yong-Hoon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.05a
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    • pp.904-907
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    • 2013
  • Demand Controller is a control device that if current electric power consumption seems to exceed the targeted amount of electric power, block the connected load devices. When this ON/OFF way is applied to electric power management of electric furnace, start and stop operation of inverter and an electric heater which supplying electric power is being performed repeatedly. This has a problem of life-shortening of inverter and an electric heater by electrical damage. In addition, when electric power supplying is blocked, attemperation is not allowed until return to normal operation condition. In this paper, we develop power management system for electric furnace using the electric furnace remote controller. This system provides the automatic control for approved electric power to electric furnace organically and prevent electric damage of inverter and an electric heater through continuous electric power supply within the targeted amount of electric power.

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Synthesis of Oxyethlyene Modified Silixoane Surfactants for Polyurethane Foam and the Characteristics of Fine Cell Formation (폴리우레탄 폼용 옥시에틸렌 변성 폴리실록산계 계면활성제의 합성 및 미세 셀 발포 특성)

  • Kim, Daeheum;Park, Seungwoo;Yeo, Seungbyung
    • Applied Chemistry for Engineering
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    • v.17 no.3
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    • pp.260-266
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    • 2006
  • For the synthesis of polyurethane memory foam stabilizer with fine cells, hydrosilylation reaction with various polyalkyleneoxides and hydrogen functional group of polymethylhydrogensiloxane (D = 75, D' = 15) was conducted. Polyalkyleneoxides (PAO) used in this research were ethylene oxides or ethylene-co-propylene oxides with terminal groups of hydroxides or methyl groups. To analyze the molecular structures and molecular weights as well as the reaction yields (98%), NMR and GPC analysis were executed. Synthesized siloxane surfactants modified with polyalkylene (EO = 12 units) were applied to producing flexible polyurethane fine memory foams from 0.6 pphp to 2.0 pphp. By controlling the amount of the surfactant, physical characteristics, the polyurethane memory foam with cell size (minimum $0.868{\mu}m$), air flows (-78 KPa), and recovery times (8 sec) were achieved.

Investigation on deck-stay interaction of cable-stayed bridges with appropriate initial shapes

  • Liu, Ming-Yi;Lin, Li-Chin;Wang, Pao-Hsii
    • Structural Engineering and Mechanics
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    • v.43 no.5
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    • pp.691-709
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    • 2012
  • This paper provides a variety of viewpoints to illustrate the mechanism of the deck-stay interaction with the appropriate initial shapes of cable-stayed bridges. Based on the smooth and convergent bridge shapes obtained by the initial shape analysis, the one-element cable system (OECS) and multi-element cable system (MECS) models of the Kao Ping Hsi Bridge in Taiwan are developed to verify the applicability of the analytical model and numerical formulation from the field observations in the authors' previous work. For this purpose, the modal analysis of the two finite element models are conducted to calculate the natural frequency and normalized mode shape of the individual modes of the bridge. The modal coupling assessment is also performed to obtain the generalized mass ratios among the structural components for each mode of the bridge. The findings indicate that the coupled modes are attributed to the frequency loci veering and mode localization when the "pure" deck-tower frequency and the "pure" stay cable frequency approach one another, implying that the mode shapes of such coupled modes are simply different from those of the deck-tower system or stay cables alone. The distribution of the generalized mass ratios between the deck-tower system and stay cables are useful indices for quantitatively assessing the degree of coupling for each mode. These results are demonstrated to fully understand the mechanism of the deck-stay interaction with the appropriate initial shapes of cable-stayed bridges.

Development of the Fashion Design of the Qing Dynasty's Clothing Style Using the Attribute Listing Technique (속성열거법을 활용한 청나라 복식스타일의 패션디자인 개발)

  • Liu, Yining;Suh, Seunghee
    • Journal of Fashion Business
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    • v.25 no.3
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    • pp.126-143
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    • 2021
  • The purpose of this study is to analyze the characteristics and design elements of the Qing dynasty costume style, and accordingly, develop a new fashion design work incorporating modern aesthetics by using the attribute listing technique. A creative idea that drew out various ideas by considering the properties and characteristics of the object in detail through applying the attribute listing technique, and a modern fashion design in the style of Qing dynasty were developed. In the design development process, first, the theme was set as 'Developing a modern fashion design using design elements of Qing dynasty costume'. Second, design elements and components focusing on design details of Qing dynasty costumes were organized. Third, design ideas that replaced or modified design elements for each type of Qing dynasty costume were presented, and the design was developed by combining and modifying these ideas. Fourth, nine designs were selected through a design evaluation process by a group of experts to select a design for the Qing dynasty costume style. Fifth, seven final designs were selected through revisions to compose a collection with unity and balance. Sixth, colour and material were decided for the selected design, and the work was completed through pattern making, sewing, and fitting process. These seven works were designed with motifs of the Qing dynasty's slit, liling, yuanling, hujian, matixiu, manxiu, shuangmanxiu, zhaixiu, pipajin, yourengquejin, yikouzhong, lingyi, yunjian, magua, mamianqun, xingshang, taoku, chaofu, xingfugua, and pao.

Engineered nanoparticles in wastewater systems: Effect of organic size on the fate of nanoparticles

  • Choi, Soohoon;Chen, Ching-Lung;Johnston, Murray V.;Wang, Gen Suh;Huang, Chin-Pao
    • Membrane and Water Treatment
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    • v.13 no.1
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    • pp.29-37
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    • 2022
  • To verify the fate and transport of engineered nanoparticles (ENP), it is essential to understand its interactions with organic matter. Previous research has shown that dissolved organic matter (DOM) can increase particle stability through steric repulsion. However, the majority of the research has been focused on model organic matter such as humic or fulvic acids, lacking the understanding of organic matter found in field conditions. In the current study, organic matter was sampled from wastewater treatment plants to verify the stability of engineered nanoparticles (ENP) under field conditions. To understand how different types of organic matter may affect the fate of ENP, wastewater was sampled and separated based on their size; as small organic particular matter (SOPM) and large organic particular matter (LOPM), and dissolved organic matter (DOM). Each size fraction of organic matter was tested to verify their effects on nano-zinc oxide (nZnO) and nano-titanium oxide (nTiO2) stability. For DOM, critical coagulation concentration (CCC) experiments were conducted, while sorption experiments were conducted for organic particulates. Results showed that under field conditions, the surface charge of the particles did not influence the stability. On the contrary, surface charge of the particles influenced the amount of sorption onto particulate forms of organic matter. Results of the current research show how the size of organic matter influences the fate and transport of different ENPs under field conditions.

Analysis of Quorum Sensing-Related Phenotypes of Pseudomonas aeruginosa Clinical Isolates (녹농균 임상균주의 쿼럼 센싱 관련 표현형 분석)

  • Jung, Kyung-Ju;Choi, Yu-Sang;Ha, Chang-Wan;Shin, Jeong-Hwan;Lee, Joon-Hee
    • Korean Journal of Microbiology
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    • v.46 no.3
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    • pp.240-247
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    • 2010
  • Pseudomonas aeruginosa is a Gram (-) opportunistic human pathogen causing a wide variety of infections on lung, urinary tract, eyes, and burn wound sites and quorum sensing (QS), a cell density-sensing mechanism plays an essential role in Pseudomonas pathogenesis. In order to investigate the importance of QS in the Pseudomonas infections of Korean patients, we isolated 189 clinical strains of P. aeruginosa from the patients in Pusan Paik Hospital, Busan, South Korea. The QS signal production of these clinical isolates was measured by signal diffusion assay on solid media using reporter strains. While most clinical strains (79.4%) produced the QS signals as similar level as a wild type strain, PAO1 did, where LasR, the initial QS signal sensor-regulator was fully activated, a minority of them (4.2%) produced much less QS signals at the level to which LasR failed to respond. Similarly, while 72.5% of the clinical isolates produced QS signals enough to activate QscR, an another QS signal sensor-regulator, some few of them (9%) produced the QS signals at much lower level where QscR was not activated. For further analysis, we selected 74 clinical strains that were obtained from the patients under suspicion of Pseudomonas infection and investigated the total protease activity that is considered important for virulence. Interestingly, significant portion of them showed very low protease activity (44.6%) or no detectable protease activity (12.2%). When the biofilm-forming ability that is considered very important in chronic infection was examined, most isolates showed lower biofilm-forming activity than PAO1. Similarly, significant portion of clinical isolates showed reduced motility (reduced swarming activity in 51.4% and reduced twitching activity in 41.9%), or non-detectable motility (swarming-negative in 28.4% and twitching-negative in 28.4%). Our result showed that the clinical isolates that produced QS signals at the similar level to wild type could have significantly reduced activities in the protease production, biofilm formation, and motility, and some clinical isolates had unique patterns of motility, biofilm formation, and protease production that are not correlated to their QS activity.

Study on the Lubricity Characteristics of Bio-heavy Oil for Power Generation by Various feedstocks (다양한 원료에 따른 발전용 바이오중유의 윤활 특성 연구)

  • Kim, Jae-Kon;Jang, Eun-Jung;Jeon, Cheol-Hwan;Hwang, In-Ha;Na, Byung-Ki
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.4
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    • pp.985-994
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    • 2018
  • Bio-heavy oil for power generation is a product made by mixing animal fat, vegetable oil and fatty acid methyl ester or its residues and is being used as steam heavy fuel(B-C) for power generation in Korea. However, if the fuel supply system of the fuel pump, the flow pump, the injector, etc., which is transferred to the boiler of the generator due to the composition of the raw material of the bio-heavy oi, causes abrasive wear, it can cause serious damage. Therefore, this study evaluates the fuel characteristics and lubricity properties of various raw materials of bio-heavy oil for power generation, and suggests fuel composition of biofuel for power generation to reduce frictional wear of generator. The average value of lubricity (HFRR abrasion) for bio-heavy oil feedstocks for power generation is $137{\mu}m$, and it varies from $60{\mu}m$ to $214{\mu}m$ depending on the raw materials. The order of lubricity is Oleo pitch> BD pitch> CNSL> Animal fat> RBDPO> PAO> Dark oil> Food waste oil. The average lubricity for the five bio-heavy oil samples is $151{\mu}m$ and the distribution is $101{\mu}m$ to $185{\mu}m$. The order of lubricity is Fuel 1> Fuel 3> Fuel 4> Fuel 2> Fuel 5. Bio-heavy oil samples (average $151{\mu}m$) show lower lubricity than heavy oil C ($128{\mu}m$). It is believed that bio-heavy oil for power generation is composed of fatty acid material, which is lower in paraffin and aromatics content than heavy oil(B-C) and has a low viscosity and high acid value, resulting in inhibition of the formation of lubricating film by acidic component. Therefore, in order to reduce friction and abrasion, it is expected to increase the lubrication of fuel when it contains more than 60% Oleo pitch and BD pitch as raw materials of bio-heavy oil for power generation.

Preference and Eating Activities of Chinese for Traditional Korean Kimchi (한국 전통 김치에 대한 중국인들의 기호도와 소비행태에 관한 연구)

  • Kim, Eun-Mi;Kim, Young-Jin;Jeong, Mi-Kyoung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.10
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    • pp.1641-1645
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    • 2004
  • The purpose of this research is to investigate Chinese's preference and directions for improvement of Kimchi by sensory evaluation, and utilize Kimchi for the China eating habit by survey. Self administered questionnaires were collected 149 Chinese (16~25 yr) residing in Shanghai. About 89.9% of all the participants had eaten Kimchi before the survey. Overall preference about Kimchi was 3.59$\pm$0.62 (5 point: Lickertis scale) and affecting factors for overall preference were taste, appearance, texture, in that order. Chinese answered that tough texture (24.9%), spicy taste (20.5%) and fermented odor (18.1%) were the most important factors in improved quality of Kimchi. They answered that applications of Kimchi with Chinese cuisine are 'side dish with meat cuisine', 'eat with cooked rice, rice-mixed-in-soup, gruel' and 'use ingredients of cook', as similar to Korean's.

A Study on Adjustment of Operational Factor in A2O process (A2O공정 운전인자 조정에 대한 연구)

  • Yoo, Ho-Sik;Lee, Byonghi
    • Journal of the Korea Organic Resources Recycling Association
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    • v.23 no.3
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    • pp.33-41
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    • 2015
  • An alternative was investigated to maximize the treatment efficiency of wastewater treatment plant without large scale expansion. 79% of detention time was required for enough nitrogen control. As aeration time was extended, nitrification was processed, but opposite trend was seen in phosphorus. High concentration of $NO_3-N$ interrupted PAOs activity not to absorb phosphorus. An alternative was devised for selective use of anaerobic or anoxic zone. Trisection was suggested for alternative use of center room. The result was relatively successful. The concentration of phosphorus was reduced with reduction of nitrogen. Extended anaerobic condition seemed to stimulate denitrification. Valve connection of internal return from aeration tank will make it possible to use middle room alternatively. This method will be a good alternative for seasonal variation of water temperature.

Removal Behavior of Biological Nitrogen and Phosphorus and Prediction of Microbial Community Composition with Its Function, in an Anaerobic-Anoxic System form Weak Sewage

  • LEE, JIN WOO;EUI SO CHOI;KYUNG IK GIL;HAN WOONG LEE;SANG HYON LEE;SOO YOOUN LEE;YONG KEUN PARK
    • Journal of Microbiology and Biotechnology
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    • v.11 no.6
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    • pp.994-1001
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    • 2001
  • An easier way of understanding the BNR system was proposed from the study on substrate, nutrient removal tendency, microbial community and its metabolic function by applying the municipal settled sewage. During the anaerobic period, the phosphorus release rate per VFACOD we varied depending on the phosphorus content in the sludge. When the phosphorus content in the sludge was $6\%$ VSS, according to influent VFACOD, the phosphorus release rate and PHA production were $0.35 gPO_4P/gVFACOD$ and 1.0 gPHA/gVFACOD, respectively. The $NO_3N$ requirement for the phosphorus uptake as an electron acceptor was about $0.5 gNO_3N/gPO_4P_{uptake}$ based on the proposed equation with PHA, biomass, production, and the concentration of phosphorus release/uptake. Bacterial-community analysis of the sludge, as determined by FISH and 16SrDNA characterization FISH, revealed that the beta-subclass proteobacteria were the most abundant group ($27.9\%$ of the proteobacteria-specific probe EUB338), and it was likely that representative of the beta-subclass played key roles in activated sludge. The next dominant group found was the gamma-protebacteria ($15.4\%$ of probe EUB338). 16S rDNA clone library analysis showed that the members of${\beta}$- and ${\gamma}$-proteobacteria were also the most abundant groups, and $21.5\%$ (PN2 and PN4) and $15.4\%$ (PN1 and PN5) of total clones were the genera of denitrifying bacteria and PAO, respectively. Prediction of the microbial community composition was made with phosphorus content (Pv, $\%$ P/VSS) in wasted sludge and profiles of COD, PHA, $PO_4P,\;and\;NO_3N$ in an anaerobic-anoxic SBR unit. Generally, the predicted microbial composition based upon metabolic function, i.e., as measured by stoichiometry, is fairly similar to that measure by the unculturable dependent method. In this study, a proposal was made on he microbial community composition that was more easily approached to analyze the reactor behavior.

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