• Title/Summary/Keyword: Breakthrough time

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Correlation of Soil Particle Distribution and Hydrodynamic Dispersion Mechanism in Ununiformed Soils Through Laboratory Column Tests (실내주상실험에 의한 불균일한 토양의 입도와 수리분산기작의 상관성 연구)

  • Kang, Dong-Hwan;Chung, Sang-Yong
    • Journal of Soil and Groundwater Environment
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    • v.11 no.6
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    • pp.28-34
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    • 2006
  • Laboratory column tests using $Cl^-$ tracer were conducted to study the correlation of soil particle distribution and hydrodynamic dispersion mechanism with three kinds of ununiformed soil samples, in which the ratio of gravel and sand versus silt and clay is 24.5 for S-1 soil, 4.48 for S-2 soil, and 0.4 for S-3 soil. Chloride breakthrough curves with time were fitted with gaussian functions. The relative concentrations of chloride were converged to 1.0 after 0.7 hours for S-1, 6.3 hours for S-2, and 389 hours for S-3. Average linear velocity, longitudinal dispersion coefficient, and longitudinal dispersivity were calculated by chloride breakthrough curves. Longitudinal dispersion coefficients were $1.20{\times}10^{-4}\;m^2/sec$ for S-1, $8.87{\times}10^{-7}\;m^2/sec$ for S-2, and $1.94{\times}10^{-9}\;m^2/sec$ for S-3. Peclet numbers calculated by the molecular diffusion coefficient of chloride and the mean grain diameters of soils were $2.59{\times}10^2$ for S-1, $6.27{\times}10^0$ for S-2, and $1.35{\times}10^{-4}$ for S-3. Mechanical dispersion was dominant for the hydrodynamic dispersion mechanism of S-1. Both mechanical dispersion and molecular diffusion were dominant for the hydrodynamic dispersion mechanism of S-2, but mechanical dispersion was ascendant over molecular diffusion. Hydrodynamic dispersion in S-3 was occurred mainly by molecular diffusion. When plotting three soils on the graph of $D_L/D_m$ versus Peclet number produced by Bijeljic and Blunt (2006), the values of $D_L/D_m$ for S-1 and S-2 were more than 2.0 order compared to their graph. S-3 was not plotted on their graph because the Peclet number was as small as $1.35{\times}10^{-4}$.

A Study on the establishment of IoT management process in terms of business according to Paradigm Shift (패러다임 전환에 의한 기업 측면의 IoT 경영 프로세스 구축방안 연구)

  • Jeong, Min-Eui;Yu, Song-Jin
    • Journal of Intelligence and Information Systems
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    • v.21 no.2
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    • pp.151-171
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    • 2015
  • This study examined the concepts of the Internet of Things(IoT), the major issue and IoT trend in the domestic and international market. also reviewed the advent of IoT era which caused a 'Paradigm Shift'. This study proposed a solution for the appropriate corresponding strategy in terms of Enterprise. Global competition began in the IoT market. So, Businesses to be competitive and responsive, the government's efforts, as well as the efforts of companies themselves is needed. In particular, in order to cope with the dynamic environment appropriately, faster and more efficient strategy is required. In other words, proposed a management strategy that can respond the IoT competitive era on tipping point through the vision of paradigm shift. We forecasted and proposed the emergence of paradigm shift through a comparative analysis of past management paradigm and IoT management paradigm as follow; I) Knowledge & learning oriented management, II) Technology & innovation oriented management, III) Demand driven management, IV) Global collaboration management. The Knowledge & learning oriented management paradigm is expected to be a new management paradigm due to the development of IT technology development and information processing technology. In addition to the rapid development such as IT infrastructure and processing of data, storage, knowledge sharing and learning has become more important. Currently Hardware-oriented management paradigm will be changed to the software-oriented paradigm. In particular, the software and platform market is a key component of the IoT ecosystem, has been estimated to be led by Technology & innovation oriented management. In 2011, Gartner announced the concept of "Demand-Driven Value Networks(DDVN)", DDVN emphasizes value of the whole of the network. Therefore, Demand driven management paradigm is creating demand for advanced process, not the process corresponding to the demand simply. Global collaboration management paradigm create the value creation through the fusion between technology, between countries, between industries. In particular, cooperation between enterprises that has financial resources and brand power and venture companies with creative ideas and technical will generate positive synergies. Through this, The large enterprises and small companies that can be win-win environment would be built. Cope with the a paradigm shift and to establish a management strategy of Enterprise process, this study utilized the 'RTE cyclone model' which proposed by Gartner. RTE concept consists of three stages, Lead, Operate, Manage. The Lead stage is utilizing capital to strengthen the business competitiveness. This stages has the goal of linking to external stimuli strategy development, also Execute the business strategy of the company for capital and investment activities and environmental changes. Manege stage is to respond appropriately to threats and internalize the goals of the enterprise. Operate stage proceeds to action for increasing the efficiency of the services across the enterprise, also achieve the integration and simplification of the process, with real-time data capture. RTE(Real Time Enterprise) concept has the value for practical use with the management strategy. Appropriately applied in this study, we propose a 'IoT-RTE Cyclone model' which emphasizes the agility of the enterprise. In addition, based on the real-time monitoring, analysis, act through IT and IoT technology. 'IoT-RTE Cyclone model' that could integrate the business processes of the enterprise each sector and support the overall service. therefore the model be used as an effective response strategy for Enterprise. In particular, IoT-RTE Cyclone Model is to respond to external events, waste elements are removed according to the process is repeated. Therefore, it is possible to model the operation of the process more efficient and agile. This IoT-RTE Cyclone Model can be used as an effective response strategy of the enterprise in terms of IoT era of rapidly changing because it supports the overall service of the enterprise. When this model leverages a collaborative system among enterprises it expects breakthrough cost savings through competitiveness, global lead time, minimizing duplication.

Clinical Study for Efficacy and Safety of Rabeprazole Sodium(Pariet) in the Treatment of Laryngopharyngeal Reflex(LPR) Disease (인후두위산역류증(Laryngopharyngeal Reflux: LPR)의 치료에 대한 RabeprazoleSodium(Parietd)의 임상효과와 안전성 검토)

  • Jung, K.W.;Jun, B.S.;Ko, S.H.;Kwon, K.H.;Kwon, S.Y.;Kwon, J.K.;Kim,, D.Y.;Kim,, S.C.;Kim,, S.W.;Kim,, Y.M.;Kim,, Y.H.;Kim,, Y.H.;Kim,, J.M.
    • Korean Journal of Bronchoesophagology
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    • v.10 no.2
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    • pp.35-42
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    • 2004
  • Background and objective : Rabeprazole is a new generation proton pump inhibitor, which has a rapid onset after first dose, predictable efficacy in all patients regardless of CYP2C19 genotype status, and less nocturnal acid breakthrough. The aim of the study is to investigate clinical efficacy and safety of rabeprazole sodium (Pariet 10mg qd)when administered once daily to patients with laryngopharyngeal reflux(LPR) disease. Methods : Among the patients who had visited the Department of Otolaryngology, those with LPR symptoms, had undergone laryngoscopy. Symptoms and endoscopic laryngeal sings were recorded initially, at 1 month, 2 months, 3 months, and more than 3 months, All patients were evaluated for clinical efficacy on the basis of symptom scores, reflux finding score(RFS), and side effects. Results : In general, most symptom scores and RFS improved over the time. Efficacy of the Pariet on LPR-related symptoms were $63.2\%,\;77.5\%,\;78.7\%,\;and\;90.9\%$ before 4 weeks, 4 to 8 weeks, 8 to 12 weeks, and after 12 weeks respectively. Efficacy on the RFS were $61.8\%,\;78.4\%,\;82.9\%,\;and\;85.5\%$ before 4 weeks, 4 to 8 weeks, 8 to 12 weeks, and after 12 weeks respectively. Pariet was well tolerated and was associated with few drug-related side effects. Conclusion Because of its efficacy and safety, Pariet may prove to be an alternative to currently available proton pump inhibitors.

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Biosorption and Development of Biosorbent by using Seaweed, Sugassum thunbergii (해조류, Sargassum thunbergii를 이용한 중금속의 바이오 흡착제의 개발)

  • SUH Kuen-Hack;LEE Hak-Sung;SUH Jung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.33 no.1
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    • pp.60-65
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    • 2000
  • Biosorptions of Cr and Pb were evaluated for 23 species of marine algae collected from a Korean coast. Among a variety of species for biosorbent potential, Sargassum species showed higher uptake capacity for Cr and Pb. An adsorption equilibrium was reached in about 1 hr for Cr and 30 min for Pb. The maximum uptake capacity was136.0 mg Cr/g biomass and 232.5 mg Pb/g biomass, respectively. In Pb biosorption in the column packed with Sargassum tbunbertii, 300 and 200 bed Tolumes at the concentration of 50 mg/L in feed solution were processed at the column residence time of 5 and 10 min before the column breakthrough point occurred. The elutions with 0.1 M HCl solution were more than $95{\%}$. The high efficiency of continous biesorntion and elution (3 cycles) indicated that Sargassum thunbergii was an effective biosorbent for Pb recovery.

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A Study on the Sorption Behavior of U(VI) ion by Arsenazo I-XAD-2 Chelating Resin (Arsenazo I-XAD-2 킬레이트수지를 이용한 U(VI) 이온의 분리 및 농축에 관한 연구)

  • Lee, Chang-Hun;Lee, Si-Eun;Lim, Jae-Hee;Eom, Tae-Yoon;Kim, In-Whan;Kang, Chang-Hee;Lee, Won
    • Analytical Science and Technology
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    • v.6 no.5
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    • pp.489-499
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    • 1993
  • Some sorption behaviors of U(VI) ion on Arsenazo I-XAD-2 chelating resin were investigated. This chelating resin was synthesized by the diazonium coupling of Amberlite XAD-2 resin with Arsenzo I chelating reagent and characterized by elementary analysis method and IR spectrometry. The optimum conditions for the sorption of U(VI) ion were examined with respect to pH, U(VI) ion concentration and shaking time. Total sorption capacity of this chelating resin on U(VI) ion was 0.39mmol U(VI)/g resin in the pH range of 4.0~4.5. This chelating resin was showed increased sorption capacity on the increased pH value. It was confirmed that sorption mechanism of U(VI) ion on the Arsenazo I-XAD-2 chelating resin was competition reacting between U(VI) ion and $H^+$ ion. Breakthrough volume and overall capacity of U(VI) ion measured by column were was 600 ml and 0.38 mmol U(VI)/g resin, respectively. The desorption of U(VI) ion was showed recovery of 90~96% using 3M $HNO_3$ and 3M $Na_2CO_3$ as a desorption solution. The separation and concentration of U(VI) ion from natural water and sea water was performed successfully by Arsenazo I-XAD-2 chelating resin.

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Characteristics of Heavy Metal Releases from the Abandoned Dogog Mine Tailing in Korea (도곡광산 광미의 중금속 용출 특성)

  • Park, Chang-Jin;Kim, Won-Il;Jeong, Goo-Bok;Lee, Jong-Sik;Ryu, Jong-Su;Yang, Jae-E.
    • Korean Journal of Environmental Agriculture
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    • v.25 no.4
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    • pp.316-322
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    • 2006
  • Objective of this research was to assess the release characteristics of metals from the mine tailing to base the prediction of metal load potential from tailing to soils. Water-soluble concentrations of Cd, Cu, Pb and Zn released from mine tailing after 2 hrs were 2.31, 129.38, 17.17, and 287.53 mg/kg, respectively, as compared to 1.6, 128, 108, and 142 mg/kg that were extractable by 0.1 M HCl. Kinetics of metal releases followed the power function model significantly indicating that more of water soluble fractions of those metals released at the initial short time, followed by a slow increase. Concentrations of metals released from tailing by water and 0.1 M HCl were in the orders of Zn > Cu > Pb > Cd. The breakthrough curve from the column experiment showed that concentrations of Cd, Cu, and Zn reached at highest after one pore volume, but that of Pb reached highest after five pore volumes when 0.1 M HCl was used as eluent. The release rate of Cd from mine tailing was the fastest but Pb was the slowest. The cumulative mass of metal released by 0.1 M HCl was in the order of Zn > Cu > Pb > Cd after nine pore volume elution.

Removal of Mixed Odor(H$_2$S/CH$_3$SH) using Char Adsorbent Made from Sewage Sludge (하수슬러지 탄화물 흡착제를 이용한 혼합 악취(H$_2$S/CH$_3$SH)의 제거)

  • Han, Young-Suk;Choi, Won-Joon;Kim, Taek-Joon;Kim, Im-Gyung;Oh, Kwang-Joong
    • Journal of Korean Society of Environmental Engineers
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    • v.30 no.11
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    • pp.1132-1138
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    • 2008
  • The study was carried out to investigate adsorption characteristic on hydrogen sulfide (H$_2$S) and methylmercaptan (CH$_3$SH) odor gas using the char made by a thermal decomposition of sewage sludge. The fixed bed adsorption experiments of the optimum L/D ratio could be 1.0, and adsorption capacity and break point increased with the increase of temperature. A simultaneous adsorption characteristic of H$_2$S and CH$_3$SH increased in breakthrough time and adsorption capacity more than single adsorption experiment, and CH$_3$SH had higher effective diffusivities than H$_2$S in same condition. The adsorption capacity of CH$_3$SH increased with fast velocity. When it was compared the produced absorbent with commercial activated carbon, As to adsorbent amount, it was H$_2$S 77% and CH$_3$SH 80% of commercial activated carbon.

Transport and Fate of Benzene in a Sandy Soil (사질토양에서의 Benzene의 이동성에 관한 연구)

  • 백두성;김동주
    • Journal of the Korean Society of Groundwater Environment
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    • v.6 no.2
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    • pp.95-100
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    • 1999
  • Hydrocarbon compounds in vadose zone soils caused by adsorption onto the surfaces of solid particles are generally considered to show retardation effect. In this study, we investigated the retardation effect on the transport of Benzene in a sandy soil by conducting batch and column tests. The batch test was conducted by equilibrating dry soil mass with Benzene solutions of various initial concentrations. and by analyzing the concentrations of Benzene in initial and equilibrated solutions using HPLC. The column test consisted of monitoring the concentrations of effluent versus time known as a breakthrough curve (BTC). We used KCl and Benzene solutions with the concentration of 10 g/L and 0.88 g/L as a tracer, and injected them into the inlet boundary of the soil sample as a square pulse type respectively, and monitored the effluent concentrations at the exit boundary under a steady state condition using an EC-meter and HPLC. From the batch test, we obtained a distribution coefficient assuming that a linear adsorption isotherm exists and calculated the retardation factor based on the bulk density and porosity of the column sample. We also predicted the column BTC curve using the retardation factor obtained from the distribution coefficient and compared with the measured BTC of Benzene. The results of the column test showed that i) the peak concentration of Benzene was much smaller than that of KCl and ⅱ) the travel times of peak concentrations for the two tracers were more or less identical. These results indicate that adsorption of Benzene onto the sand panicles occurred during the pulse propagation but the retardation of Benzene caused by adsorption was not present in the studied soil. Comparison of the predicted with the measured BTC of Benzene resulted in a poor agreement due to the absence of the retardation phenomenon. The only way to describe the absolute decrease of Benzene concentration in the column leaching experiment was to introduce a decay or sink coefficient in the convection-dispersion equation (CDE) model to account for an irreversible sorption of Benzene in the aqueous phase.

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Experiment and Simulation of 4-bed PSA for Hydrogen Separation from Multi-Component Mixture Gases (다성분 혼합 기체로부터 수소 분리를 위한 4-bed PSA 실험과 전산 모사)

  • Yang, Se-Il;Park, Ju-Yong;Jang, Seong-Cheol;Choi, Do-Young;Kim, Sung-Hyun;Choi, Dae-Ki
    • Korean Chemical Engineering Research
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    • v.46 no.2
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    • pp.414-422
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    • 2008
  • Adsorption experiments for $H_2$, $CH_4$, CO, $CO_2$ on activated carbon and zeolite 5A were performed by static volumetric method. A 4-bed pressure swing adsorption (PSA) process was to study separation of hydrogen from multi-component mixture gases ($H_2$ 72.2%, $CH_4$ 4.06%, CO 2.03%, $CO_2$ 21.6%). Dual-site langmuir (DSL) isotherm showed good or fair agreement with the experimental results. The optimum height of activated carbon layer was 55 cm with breakthrough results on the packing ratio of activated carbon to zeolite 5A. In PSA process, the effects of the process parameters such as total cycle time ($T_c$), ${\Delta}P$ at the provide purge step and adsorption pressure on the PSA performance were studied experimentally and theoretically.

Analysis of Pain Records for Cancer Patients Complaining of Moderate or Severe Pain (중등도 이상의 통증을 호소하는 암환자의 통증간호기록 분석)

  • Park, Ran Hee;Cho, Ok Hee;Yoo, Yang Sook
    • Journal of Hospice and Palliative Care
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    • v.17 no.4
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    • pp.270-277
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    • 2014
  • Purpose: This is a retrospective study that investigated cancer patients' complaints of moderate or severe pain to analyze pain characteristics, pain relief interventions and their effects. Methods: The participants of this study were 363 patients who were hospitalized in the cancer ward for three to 30 days and scored 4 points or higher on the pain severity assessment. Results: The most frequent region of pain was the abdomen. The most frequent factor that exacerbated pain was movement. The most frequent pain alleviating factor was administration of analgesics. The most frequent pain type was breakthrough pain, and the most frequent non-pharmaceutical intervention for pain control was heat therapy. Among all, analgesics were routinely prescribed for 52.2% of the participants. Morphine sulfate was the most frequently used analgesic while Gabapentin was the most frequently used non-narcotic analgesic. At the time of discharge, 82.5% of the participants marked their pain intensity as 3 points or lower. Conclusion: For cancer patients complaining of moderate or severe pain, it is important to actively control pain from the beginning of admission. Thus, it is necessary to educate not only cancer patients using narcotic analgesic for pain control and their families but nurses about the effects and side-effects of drugs. Moreover, patients and their families need to learn how to assess and record pain at home to collect data that can be referred for future treatment.