• Title/Summary/Keyword: active pressure

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Removal Characteristics of Nitrogen Oxides (NOx) in Low Concentration using Peat-Mixed Media (피트(peat) 혼합담체를 이용한 저농도 질소산화물(NOx) 제거특성)

  • Kang, Young-Heoun;Kim, Deok-Woo;Kang, Seon-Hong;Kwon, Pil-Joo;Kim, Dal-Woo;Hwang, Pil-Gi;Shim, Sang-Bo
    • Journal of Korean Society for Atmospheric Environment
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    • v.26 no.3
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    • pp.330-338
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    • 2010
  • In this study, removal characteristics of nitrogen oxides $(NO_x)$ from road transport by using peat as the packing media for biodegradation have been investigated in the long term. Physicochemical and biological treatment of peatmixed media eliminates any requirement to use chemical substances and also facilitates the biodegradable actions of microorganism. Safe biodegradation of pollutants, no need to apply additional microbes owing to their active growth, and no generation of secondary pollutants were found in this experiment. It was concluded that average removal efficiencies of nitric oxide (NO) and nitrogen dioxide $(NO_2)$ were 80% and 97% respectively with respect to the linear velocity 35~40 mm/s and 0.3 ppm ozone concentration in the long period operation. Inflow concentration of nitric oxide over 0.05 ppm was suitable when pretreated with ozone. Non-ozone stage was performed with linear velocity 20~100 mm/s and then the average removal efficiency of nitric oxide and nitrogen dioxide were 38% and 94% respectively. Other results showed that the apparent static pressure was raised with increases in applied water content and aerial velocity in mixed media during fan operation.

Photolysis Improvement of Toluene in 50%TiO2/6%WO3 Sol Solutions Sensitized by Acetone (50%TiO2/6%WO3 졸 용액에서의 톨루엔 처리에 대한 아세톤의 광활성 증가효과)

  • Shin, Hye-Seung;Kim, Jae-Hyoun
    • Journal of Environmental Health Sciences
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    • v.38 no.3
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    • pp.261-268
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    • 2012
  • Objectives: The photocatalytic degradation of toluene in a batch mode photoreactor for the purpose of the hazardous waste treatment was investigated. Methods: Kinetic experiments using a low pressure mercury lamp (Lambda Scientific Pty Ltd, 50 Watt) emitting both UV and visible light were performed at $31^{\circ}C$ over toluene concentrations ranging from 10 to 50 mg/l in water with $50%TiO_2/6%WO_3$ (TW) concentration of 1 g/l at a pH of 6. Results: Kinetic studies showed that $50%TiO_2/6%WO_3$ (TW) photocatalyst was highly active in toluene degradation; we observed that 99% of the pollutant was degraded after six hours under visible irradiation; furthermore, we observed that adsorption onto TW catalyst was responsible for the decrease of toluene with pseudo-first order kinetics. It was also found that oxygen as a radical source in the sol medium played a significant role in affecting the photodegradation of toluene, especially with a two-fold elevation. This increase was achieved by a more than four-fold elevation of the photodegradation of toluene in the presence of acetone than without, presumably via an energy transfer mechanism. Conclusions: We concluded that photodegradation in acetone and oxygen molecules along with TW was an effective method for the removal of toluene from wastewater.

A Study of the Dead Man's Switch considering bio-response (생체 신호를 이용한 기관사 감시시스템 연구)

  • Song, Yong-Soo;Baek, Jong-Hyen;Ko, Tae-Kyun;Kim, Yong-Kyu
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.165-171
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    • 2011
  • A Consider the dead man's switch installed in each and every locomotive cab, which support operational safety on railways around the world. The concept is very simple - every 150 to 180 seconds an illuminated push-button demands to be acknowledged so as to know that the Train Driver is alive and active. In the absence of a response over a period of minutes, the vigilance control will automatically apply the train brakes and bring the train to a stand. If we multiply the resetting of the vigilance control 60 times per hour by a 10-hour shift it equals 600 presses of the button during the shift that a Train Driver must pay attention to and acknowledge. This adds a fair bit of pressure on the train driver's job, particularly when he/she is driving through stations, with passengers moving about on platforms in an environment of complex signaling arrangements - all the while looking out for restricting signals. From this perspective, the Vigilance System's demand to be acknowledged every 150/180 seconds is disturbing and can unnecessarily take a driver's attention away from what is happening outside the confines of the cab. A much more dramatic situation can happen when a train driver is driving hour after hour at night when, by Mother's Nature request - people need to sleep. Experience and research shows that the the dead man's switch can be pressed by train driver in a state of deep relaxation and 'micro-sleep'. The vigilance control system which is applied to reduce the drive load considering bio-response multiple unit train is proposed.

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Implementation of Ontology-based Clinical Decision Support System for Management of Interactions Between Antihypertensive Drugs and Diet (항고혈압제-식이 상호작용 관리를 위한 온톨로지 기반의 임상의사결정지원시스템 구현)

  • Park, Jeong-Eun;Kim, Hwa-Sun;Chang, Min-Jung;Hong, Hae-Sook
    • Journal of Korean Academy of Nursing
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    • v.44 no.3
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    • pp.294-304
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    • 2014
  • Purpose: The influence of dietary composition on blood pressure is an important subject in healthcare. Interactions between antihypertensive drugs and diet (IBADD) is the most important factor in the management of hypertension. It is therefore essential to support healthcare providers' decision making role in active and continuous interaction control in hypertension management. The aim of this study was to implement an ontology-based clinical decision support system (CDSS) for IBADD management (IBADDM). We considered the concepts of antihypertensive drugs and foods, and focused on the interchangeability between the database and the CDSS when providing tailored information. Methods: An ontology-based CDSS for IBADDM was implemented in eight phases: (1) determining the domain and scope of ontology, (2) reviewing existing ontology, (3) extracting and defining the concepts, (4) assigning relationships between concepts, (5) creating a conceptual map with CmapTools, (6) selecting upper ontology, (7) formally representing the ontology with Protege (ver.4.3), (8) implementing an ontology-based CDSS as a JAVA prototype application. Results: We extracted 5,926 concepts, 15 properties, and formally represented them using Protege. An ontology-based CDSS for IBADDM was implemented and the evaluation score was 4.60 out of 5. Conclusion: We endeavored to map functions of a CDSS and implement an ontology-based CDSS for IBADDM.

Complete Oxidation of Volatile Organic Compounds(BTX) over the Supported Transition Metal Catalysts (전이금속 담지 촉매상에서 휘발성유기화합물(BTX)의 완전산화)

  • Kim, Sang-Chai;Seo, Seong-Gyu;Yu, Eui-Yeon
    • Clean Technology
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    • v.6 no.1
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    • pp.17-25
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    • 2000
  • Catalytic oxidation of volatile organic compounds(benzene, toluene, xylene) over transition metals/ALO-6 catalysts was investigated in a fixed bed flow reactor system at atmospheric pressure. The orders of catalytic activities for the complete oxidation of toluene were Cu>Mn>Fe>V>Mo>Co>Ni>Zn for 15% transition metals/ALO-6 catalyst system. Increasing the calcination temperature resulted in decreasing the specific surface areas of catalyst, subsequently the catalytic activity. The loading of Cu on ALO-6 had a great effect on the catalytic activity and 5% Cu/ALO-6 catalyst showed higher catalytic activity, which may be contributed to the uniformly distributed active sites. Benzene, toluene and xylene were completely oxidized to carbon dioxide over 5% Cu/ALO-6 catalyst at over $380^{\circ}C$ and 4.5 g-cat.hr./g-mole. The orders of the kinds of reactants for catalytic activity over 5% Cu/ALO-6 were toluene>xylene>benzene. As the concentration of reactant increased, the catalytic activity decreased due to self-poison of reactant.

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Analysis of ICU Treatment on Resection of Giant Tumors in the Mediastinum of the Thoracic Cavity

  • Kang, Nai-Min;Xiao, Ning;Sun, Xiao-Jun;Han, Yi;Luo, Bao-Jian;Liu, Zhi-Dong
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.6
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    • pp.3843-3846
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    • 2013
  • Objective: The purpose of this study was to assess prognosis after resection of giant tumors (including lobectomy or pneumonectomy) in the mediastinum. Materials and Methods: Patients with resection of a giant tumor in the mediastinum of the thoracic cavity received ICU treatment including dynamic monitoring of vital signs, arterial blood pressure and CVP detection, determination of hemorrhage, pulmonary function and blood gas assay, treatment of relevant complications, examination and treatment with fiber optic bronchoscopy, transfusion and hemostasis as well as postoperative removal of ventilators by invasive and non-invasive sequential mechanical ventilation technologies. Results: Six patients were rehabilitated successfully after ICU treatment with controlled postoperative errhysis and pulmonary infection by examination and treatment with fiber optic bronchoscopy without second application of ventilators and tubes after sequential mechanical ventilation technology. One patient died from multiple organ failure under ICU treatment due to postoperative active hemorrhage after second operative hemostasis. Conclusions: During peri-operative period of resection of giant tumor (including lobectomy or pneumonectomy) in mediastinum ofthe thoracic cavity, the ICU plays an important role in dynamic monitoring of vital signs, treatment of postoperative stress state, postoperative hemostasis and successful removal of ventilators after sequential mechanical ventilation.

A Study on Interim Measures of Arbitration - the Korea domestic perspective - (중재에서의 임시적처분에 대한 연구 - 국내 중재를 중심으로 -)

  • Choi, An-Sik
    • Journal of Arbitration Studies
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    • v.30 no.2
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    • pp.121-144
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    • 2020
  • If the interim disposition of the Arbitration Tribunal is not immediately enforceable, it will only give pressure to the other party concerned and the arbitration could work against him if the other party fails to implement it. If enforcement is impossible, the disposition will have no practical effect or practical benefit. In addition, if a system is contrary to its unique characteristics or nature, it will not function as a system or it will become an unnecessary decoration. There is no room for argument that the above provisions are wrong or misinterpreted if the temporary disposition in arbitration cannot be characterized by its characteristics, such as its provisionality, urgency, incidentality, or invasibility. As attracting international arbitration cases can create enormous added value for the national economy, countries are scrambling to create a mediating-friendly legal environment in their countries, and Korea has been more active in arbitration than in the past. Despite various efforts, however, attracting international arbitration cases is still a long way off. Therefore, Korea should create a mediating-friendly, legal environment to attract arbitration cases. There are many reasons why arbitration is activated internationally, but the most important of them is that it is easier to approve and execute. The use of the approval and execution of heavy court is, in turn, the most important requirement of a mediating-friendly environment. It is natural that temporary dispositions made in arbitration should be as easy to approve and enforce as in the case of arbitration. In addition, it is natural for the parties to consider the use of approval and execution when deciding where to mediate or when applying for arbitration; thus, the degree of ease of execution, along with the procedural use of arbitration or provisional disposition, will be a measure of the likelihood of hosting international arbitration cases, as well as the activation of arbitration.

Simulation Study on the Application of LNG Cold Energy for Hydrogen Liquefaction Process (수소액화공정에서 LNG 냉열 적용에 관한 시뮬레이션 연구)

  • HAN, DANBEE;BYUN, HYUNSEUNG;BAEK, YOUNGSOON
    • Transactions of the Korean hydrogen and new energy society
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    • v.31 no.1
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    • pp.33-40
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    • 2020
  • As hydrogen utilization becomes more active recently, a large amount of hydrogen should be supplied safely. Among the three supply methods, liquefied hydrogen, which is an optimal method of storage and transportation convenience and high safety, has a low temperature of -253℃, which is complicated by the liquefaction process and consumes a lot of electricity, resulting in high operating costs. In order to reduce the electrical energy required for liquefaction and to raise the efficiency, hydrogen is cooled by using a mixed refrigerant in a precooling step. The electricity required for the precooling process of the mixed refrigerant can be reduced by using the cold energy of LNG. Actually, LNG cold energy is used in refrigeration warehouse and air liquefaction separation process, and a lot of power reduction is achieved. The purpose of this study is to replace the electric power by using LNG cold energy instead of the electric air-cooler to lower the temperature of the hydrogen and refrigerant that are increased due to the compression in the hydrogen liquefaction process. The required energy was obtained by simulating mixed refrigerant (MR) hydrogen liquefaction system with LNG cold heat and electric system. In addition, the power replacement rate of the electric process were obtained with the pressure, the temperature of LNG, the rate of latent heat utilization, and the hydrogen liquefaction capacity, Therefore, optimization of the hydrogen liquefaction system using LNG cold energy was carried out.

Influence on the Ground Reaction Force Parameters According to Wearing Positions of Backpacks During Stair Ascending and Descending (계단 오르기와 내리기 시 가방착용 위치가 지면반력 파라미터에 미치는 영향)

  • Hyun, Seung-Hyun;Ryew, Che-Cheong
    • Korean Journal of Applied Biomechanics
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    • v.25 no.1
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    • pp.85-94
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    • 2015
  • Purpose : The purpose of this study was to investigate the influence on the ground reaction force parameters according to wearing positions of backpack for during stair ascending and descending. Methods : Participants selected as subject were consisted of young female(n=10) and performed stairs walks(ascending and descending) with 2 types of wearing position(front of trunk[FT], rear of trunk[RT]). Passive(Fz 1) and active(Fz 2) forces of the vertical GRF were determined from time function and frequency domain. Also shear forces(Fx, Fy 1, Fy 2), dynamic postural stability index(MLSI, APSI, VSI, DPSI), loading rate and center of pressure (${\Delta}COPx$, ${\Delta}COPy$, COP area) were calculated from time function and frequency domain. Results : Fx, Fy 1, Fy 2, and Fz 1 in GRF didn't show significant differences statistically according to the wearing positions of backpack(p>.05), but stair descending showed higher forces than that of stair ascending. Particularly, Fz 2 of stair ascending showed higher forces than that of stair descending(p<.001), RT types showed higher than that of FT types(p<.05). MLSI, APSI, VSI, and DPSI of stair descending showed the increased stability index than that of stair ascending(p<.05), MLSI of RT types showed the decreased stability index than that of FT types(p<.05). Loading rate didn't show significant differences statistically according to the wearing positions of backpack(p>.05), but stair descending showed higher loading rate than that of stair ascending(p<.001). Also, ${\Delta}COPx$ in stair descending showed the increased movement than that of stair ascending(p<.05). Conclusions : A backpack of 10 kg(10 kg(ratio of body weights $17.61{\pm}1.17%$) showed significantly change GRF parameters according to wearing positions during stair ascending and descending. If possible, we suggest that the dynamic stability, in case of stairs walking with a smaller weights can be further improved.

Study on the Partial Hydrogenation of Butadiene over Highly Dispersed Supported Gold Catalysts (고분산 담지 금 촉매에 의한 Butadiene의 부분 수소화에 관한 연구)

  • Ahn, Ho-Geun;Hiroo, Niiyama
    • Applied Chemistry for Engineering
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    • v.10 no.7
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    • pp.1003-1007
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    • 1999
  • The activity and products distribution for the hydrogenation of butadiene and pentadiene over the gold and cobalt catalysts prepared by coprecipitation and impregnation method was investigated with using a flow reactor under atmospheric pressure. The reaction characteristics of the highly dispersed gold particles and its role were studied. The activity of the gold catalyst by coprecipitation was much higher than that by impregnation. The selectivity of butene on all gold particles was always 100% even in the absence of butadiene in the stream, but butadiene on cobalt supported catalyst was easily hydrogenated to butane. It was therefore considered that the active sites at circumferences of the gold particles possessed an unique property which took a proper affinity to hydrogen. In the hydrogenation of butadiene and pentadiene, the percentages of 1-butene and 2-pentene were 60%~70% and about 62%, respectively. The results could be simply explained by a statistical concepts of hydrogen addition.

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