• Title/Summary/Keyword: engineering optimization

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Preparation and Reactivity of ZnO-Al$_2$O$_3$ Desulfurization Sorbents for Removal H$_2$S ($H_2S$제거를 위한 ZnO-$Al_2O_3$ 탈황제의 제조 및 반응특성 연구)

  • 박노국;이종욱;류시옥;이태진;김재창
    • Journal of Energy Engineering
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    • v.11 no.2
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    • pp.136-141
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    • 2002
  • Advanced zinc-based sorbents, ZA, for Hot Gas Desulfurization (HGD) process in Integrated Gasification Combined Cycle (IGCC) systems were formulated with $Al_2$O$_3$ as support to enhance the reactivity and their reactive characteristics was also investigated in this study. Changes in the physical and chemical properties of the sorbents based on both the mole ratios of ZnO/Al$_2$O$_3$ and the calcination temperatures were examined by a XRD. The results obtained in our desulfurization-regeneration cycle tests demonstrated that degradation of sorbents due to the heat generation could be improved through the optimization of the $Al_2$O$_3$ contents and of the calcination temperatures. From the durability study it is concluded that the prepared ZA sorbents with additives have the desirable features for HGD.

A Long Term Market Forecasting of Passenger Car using MESSAGE Modelling (MESSAGE 모델링을 이용한 승용차 부문의 그린카 도입 전망 분석)

  • Yoo, Jong-Hun;Kim, Hu-Gon
    • Journal of Energy Engineering
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    • v.21 no.1
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    • pp.33-42
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    • 2012
  • In this study, long-term greenhouse gas reductions expected passenger sector was used for the MESSAGE. Green Car road map proposed BAU scenario, Enhanced diffusion green car scenario, and price 1, 2 scenarios was configured with four scenarios. Enhanced diffusion green car in the scenario, in 2050 compared to BAU scenario 13% of the emissions will decrease. Price 1 and Price 2 scenario is emissions reduction of 14% compared to BAU. This study consists of six chapters. Introduction of MESSAGE, creation and RES in the year and the target year set a different base line and the passenger building materials sector activities, steps for passenger sector scenario and Based on the results of running the emissions reductions were to describe.

A Study on High-Resolution Technique in MRI Scan for Cerebral Aneurysm Disease -Comparison between High-Resolution Technique and Standard Technique- (뇌 동맥류 질환 자기공명검사에서 고분해능(High-Resolution) 기법의 관한 연구 - 고분해능기법과 표준기법 비교 -)

  • Choi, Sung-Hyun;Goo, Eun-Hoe;Hwang, Sun-Kwang;Lee, Gang-Won;Lee, Jong-Woong
    • Korean Journal of Digital Imaging in Medicine
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    • v.14 no.1
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    • pp.7-12
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    • 2012
  • The purpose of this study was to examine usefulness of 3T equipment-based time-of-flight magnetic resonance angiography (3T-TOF MRA) by comparing standard technique (ST) with high resolution technique (HRT) in evaluation of cerebral blood vessel. The 3T-TOF MRA was performed for 31 patients who were suspected of having cerebrovascular disease from March to July 2010. For evaluation of cerebral blood vessel, classification was conducted randomly: group I that included vertebral artery and basilar artery, group II that ranged from 2.5cm before basin part of common carotid artery to basin part of internal and external carotid arteries and to genu part of internal carotid artery, group III that ranged from vertebral part of internal carotid artery to the first basin art of anterior and middle cerebral through education recognizes the importance of dose reduction and examine if their efforts and further reduce patient dose could achieve optimization of the medical exposure is considered.

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Implementation of H.264/SVC Decoder Based on Embedded DSP (임베디드 DSP 기반 H.264/SVC 복호기 구현)

  • Kim, Youn-Il;Baek, Doo-San;Kim, Jae-Gon;Kim, Jin-Soo
    • Journal of Broadcast Engineering
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    • v.16 no.6
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    • pp.1018-1025
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    • 2011
  • Scalable Video Coding (SVC) extension of H.264/AVC is a new video coding standard for media convergence by providing diverse videos of different spatial-temporal-quality layers with a single bitstream. Recently, real-time SVC codecs are being developed for the application areas of surveillance video and mobile video, etc. This paper presents the design and implementation of a H.264/SVC decoder based on an embedded DSP using Open SVC Decoder (OSD) which is a real-time software decoder designed for the PC environment. The implementation consists of porting C code of the OSD software from PC to DSP environment, profiling the complexity performance of OSD with further optimization, and integrating the optimized decoder into the TI Davinci EVM (Evaluation Module). 50 QCIF/CIF frames or 15 SD frames per second can be decoded with the implemented DSP-based SVC decoder.

Improvement of Tropane Alkaloid Productivity by Optimization of Sucrose Concentration and Addition of Hydroxyapatite in Hairy root Cultures of Scopolia parviflora (미치광이풀 모상근 배양에서 적정 sucrose 농도 및 hydroxyapatite 첨가에 의한 tropane alkaloid 생산성 향상)

  • An, Jun-Chul;Yang, Sun-Ju;Pyo, Byung-Sik;Choi, Ji-Won;Hwang, Baik
    • Korean Journal of Plant Tissue Culture
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    • v.25 no.1
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    • pp.21-25
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    • 1998
  • The effects of sucrose concentration and some absorbents on growth and tropane alkaloid production in hairy root cultures of Scopolia parviflora were investigated. The maximum effect on growth and tropane alkaloid production in hairy root clone SP11 was obtained for 1/2 B5 medium containing 5% sucrose. The production pattern of tropane alkaloid in hairy roots was some different from that of rhizome of mother plant, particulary showing high littorine contents, which was not found in ordinary roots. Among absorbents examined, charcoal 0.01% and XAD-II 1% made a slight growth promotion effect, whereas the other concentration of charcoal, XAD-II and absorbents (amberlite and chitosan) showed inhibition or no significant effect. The addition of hydroxyapatite enhanced the production of tropane alkaloids significantly than control cultures.

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Photodynamic Therapy for Neoplasms in Intrathoracic Constructed Stomach (식도암 수술 후 흉곽 내 위장에 발생한 원발성 위암에 대한 광역동치료 -1예 보고 -)

  • Park, Ki-Sung;Ko, Moo-Sung;Kwon, Oh-Choon;Lee, Sub;Kim, Jong-Ki;Jheon, Sang-Hoon
    • Journal of Chest Surgery
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    • v.36 no.10
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    • pp.794-797
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    • 2003
  • Photodynamic therapy (PDT) is a local, endoscopically controlled nonoperative therapeutic technique based on selective sensitization of mucosal, malignant and precancerous lesions of the esophagus, trachea and bronchus prior to light-induced tissue destruction in the department of thoracic and cardiovascular surgery. PDT is effective and safe for palliative treatment of neoplasms in the stomach, esophagus, and lung. But skin phototoxicity is unsatisfactory, therefore optimization of management of post-PDT is necessary for preventing phototoxic side effects of skin. Careful patient education in photoprotection techniques, close patient follow-up, early dermatologic referral and medical treatment are recommended. We performed PDT in a patient with intrathoracic constructed stomach. We report this case with a brief review of literatures, therefore.

Seismic Response Characteristics of Submerged Systems with Large Hydrodynamic Effect in Base-isolated Structure (지진절연 건물내 유체동적효과가 큰 수중계의 지진응답특성)

  • Shin, Tae-Myung;Kim, Kwang-Joon
    • Journal of KSNVE
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    • v.7 no.4
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    • pp.655-661
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    • 1997
  • Base-isolation of a primary structure generally decrete the seismic response of its own and the secondary structure. It may cause an adverse effect on the seismic response of secondary system when the system is submerged and subject to a considerable hydrodynamic effect. In this paper, it is shown how, and how much, the base isolation of the primary structure can affect the secondary system response in extreme cases through dynamic analysis of a simplified coupled model for a submerged secondary system and a base-isolated primary structure. As an aseismatic design approach to reduce the response of the submerged system, optimization of the fluid gap, which controls the hydrodynamic mass effect, is performed. As an alternative approach in case where the control of fluid gap is unrealistic, application of base isolation to the submerged system is suggested. Effectiveness of various combinations of the primary base and secondary base isolations are compared.

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Optimization of Cellulose Dyeing with Natural Indigo: Ramie dyeing by One-step Reduction/dyeing Process (천연인디고를 이용한 셀룰로오스계 직물 염색의 표준화 연구: 일단계 환원/염색에 의한 마직물 염색)

  • Son, Kyung-Hee;Shin, Youn-Sook;Yoo, Dong-Il
    • Fashion & Textile Research Journal
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    • v.13 no.2
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    • pp.263-268
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    • 2011
  • One-step reduction/dyeing method was applied for ramie dyeing with natural indigo powder. The effect of reduction/dyeing conditions including the pH of bath, dye temperature and time, and concentration of indigo powder and reduction agent on dye uptake and color properties were investigated. Regardless of addition of alkali, the dyed fabrics appeared in the PB Munsell color range(${\lambda}_{max}$: 660 nm) and the dye uptake was much higher with no addition of sodium hydroxide. Dyeing was carried out through the use of only sodium hydrosulfite in the bath. The maximum dye uptake was obtained at 60 for 30min. Saturated dye uptake was obtained at 2 g/L of sodium hydrosulfite concentration up to 2 g/ L of indigo powder. Whereas, at higher indigo powder concentration (4 g/L), more than 3 g/L of reducing agent concentration was required for obtaining the saturated dye uptake. Color reproducibility was reliable with color difference in the range of 0.03~0.16. Regardless of color strength, fastness to rubbing was acceptable with a 3/4~4/5. Fastness to washing, dry cleaning, and light of samples with low color strength were poor. Whereas, fastness to washing, dry cleaning, and light of samples with high color strength were very good.

Study on Friction Welding of Torsion Bar Material(1) -Optimization of Friction Welding Technique- (토션 바재의 마찰용접에 관한 연구(I) -마찰용접기술의 최적화에 대하여-)

  • 오세규;이종두
    • Journal of Ocean Engineering and Technology
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    • v.4 no.1
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    • pp.101-109
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    • 1990
  • The friction welding has more technical and economic advantages than the other welding processes. As this welding process has the characteristics such as curtailment of production time, materials, cost reduction, etc., it has been widely used in production of various mechanical components which have complex shapes. So, this paper deals with optimizing the friction welding conditions and analyzing various mechanical properties of the friction welded joints of torsion bar material SUP9A bar to bar. The results obtained are summarized as follows; 1) The quantitative relation between heating time($t_{1}$, sec) and total upset(U, mm)can be obtained. The empirical formula obtained is ; U = 3.29$t_{1}$ + 1.6 2) The tensile strength($\sigma_{t}$, kgf/$mm^{2}$) of friction welding joints as post weld heat treated(PWHT) depends upon heating time($t_{1}$, sec) quantitatively and the empirical formula obtained is ; $\sigma$= -5.1$t_{1}\;^{2}$+44.90$t_{1}$+45.2 3) It is certain that the optimum condition for friction welded joints of SUP9A steel bars of diameter 14.5mm is, considering on various properties such as tensile strength, torsional strength, impact energy and strain of the joints after PWTH ; n = 2000rpm, $P_{1}$=8kgf/$mm^{2}$, $P_{2}$=20kgf/$mm^{2}$, $t_{1}$=4sec, $t_{2}$=3sec 4) The tensile strength, torsional strength and hardness were increased with the increased with the increasing carbon equivalent, but toughness was decreased.

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Hybrid Genetic Operators of Hamming Distance and Fitness for Reducing Premature Convergence (조기수렴 저감을 위한 해밍거리와 적합도의 혼합 유전 연산자)

  • Lee, Hong-Kyu
    • Journal of Advanced Navigation Technology
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    • v.18 no.2
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    • pp.170-177
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    • 2014
  • Genetic Algorithms are robust search and optimization techniques but have some problems such as premature convergence and convergence to local extremum. As population diversity converges to low value, the search ability decreases and converges to local extremum but population diversity converges to high value, then the search ability increases and converges to global optimum or genetic algorithm may diverge. To guarantee that genetic algorithms converge to the global optima, the genetic operators should be chosen properly. In this paper, we propose the genetic operators with the hybrid function of the average Hamming distance and the fitness value to maintain the diversity of the GA's population for escaping from the premature convergence. Results of simulation studies verified the effects of the mutation operator for maintaining diversity and the other operators for improving convergence properties as well as the feasibility of using proposed genetic operators on convergence properties to avoid premature convergence and convergence to local extremum.