• Title/Summary/Keyword: U-Product

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DEVELOPMENT OF PYROPROCESSING AND ITS FUTURE DIRECTION

  • Inoue, Tadashi;Koch, Lothar
    • Nuclear Engineering and Technology
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    • v.40 no.3
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    • pp.183-190
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    • 2008
  • Pyroprocessing is the optimal means of treating spent metal fuels from metal fast fuel reactors and is proposed as a potential option for GNEP in order to meet the requirements of the next generation fuel cycle. Currently, efforts for research and development are being made not only in the U.S., but also in Asian countries. Electrorefining, cathode processing by distillation, injection casting for fuel fabrication, and waste treatment must be verified by the use of genuine materials, and the engineering scale model of each device must be developed for commercial deployment. Pyroprocessing can be effectively extended to treat oxide fuels by applying an electrochemical reduction, for which various kinds of oxides are examined. A typical morphology change was observed following the electrochemical reduction, while the product composition was estimated through the process flow diagram. The products include much stronger radiation emitter than pure typical LWR Pu or weapon-grade Pu. Nevertheless, institutional measures are unavoidable to ensure proliferation-proof plant operations. The safeguard concept of a pyroprocessing plant was compared with that of a PUREX plant. The pyroprocessing is better adapted for a collocation system positioned with some reactors and a single processing facility rather than for a centralized reprocessing unit with a large scale throughput.

A Study for Defense Acquisition System Improvement (국방무기체계 획득절차 발전방향 - 미국 국방획득절차 개선노력을 중심으로 -)

  • Go, Sim-Jae
    • Journal of the military operations research society of Korea
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    • v.31 no.2
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    • pp.86-104
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    • 2005
  • During the 'Cold War', DoD had focused on the high performance and timely acquisition which enabled quick field out the superior weapons than the enemy regardless of acquisition cost. But, after the cold war, the focus has been changed to the 'cost effective acquisition' of weapon systems because of tremendous investment cost & economic theory. The U.S. DoD has been tried to make 'the most effective acquisition system'(AR, Acquisition Reform) from mid-80's with their enough experienced program data, and as a result, they had launched the new acquisition procedure - DoD 5000 series - in 1996. DoD is continuously doing the study and making several improvements on the procedure after it had been once announced. On Oct 30. 2002, DoD noticed that they cancelled the DoD 5000 series documents(5000.1, 5000.2, 5000.2-R) and 5000.2-R will be reissued as a guide. The most recent version which focused on 1) evolutionary acquisition and spiral development, 2) procedure for future technology systems including software and IT, 3) supplement on the area of efficiency, flexibility, creativity and innovation of old system was issued by May 12. 2003. This article suggests a 'good idea' based on the reviewing of these DoD efforts for our defense acquisition regulation and procedure to go. It includes the CAIV concept application, IPT utilization, T&E method, cost or price based contract etc-all for the effective acquisition.

Web Enabled Expert Systems using Hyperlink-based Inference

  • Yong U. Song;Kim, Wooju;June S. Hong
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2003.05a
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    • pp.319-328
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    • 2003
  • With the proliferation of WWW, providing more intelligence to Web sites has become a major concern in e-business industry. In recent days, this trend is more accelerated by prosperity of CRM (Customer Relationship Management) in terms of various aspects such as product recommendation, self after service, etc. To accomplish this goal, many e-companies are eager to embed web enabled rule-based system, that is, expert systems into their Web sites and several well-known commercial tools are already available in the market. Most of those tools are developed based on CGI so far but CGI based systems inherently suffer over-burden problem when there are too many service demands at the same time due to the nature of CGI. To overcome this limitation of the existing CGI based expert systems, we propose a new form of Web-enabled expert system using hyperlink-based inference mechanism. In terms of burden to Web server, our approach is proven to outperform CGI based approach theoretically and also empirically. For practical purpose, our this approach is implemented in a software system, WeBIS and a graphic rule editing methodology, Expert Diagram is incorporated into the system to facilitates rule generation and maintenance. WeBIS is now successfully operated for financial consulting in the web site of a leading financial consulting company in Korea.

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Effect of CrN barrier on fuel-clad chemical interaction

  • Kim, Dongkyu;Lee, Kangsoo;Yoon, Young Soo
    • Nuclear Engineering and Technology
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    • v.50 no.5
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    • pp.724-730
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    • 2018
  • Chromium and chromium nitride were selected as potential barriers to prevent fuel-clad chemical interaction (FCCI) between the cladding and the fuel material. In this study, ferritic/martensitic HT-9 steel and misch metal were used to simulate the reaction between the cladding and fuel fission product, respectively. Radio frequency magnetron sputtering was used to deposit Cr and CrN films onto the cladding, and the gas flow rates of argon and nitrogen were fixed at certain values for each sample to control the deposition rate and the crystal structure of the films. The samples were heated for 24 h at 933 K through the diffusion couple test, and considerable amount of interdiffusion (max. thickness: $550{\mu}m$) occurred at the interface between HT-9 and misch metal when the argon and nitrogen were used individually. The elemental contents of misch metal were detected at the HT-9 through energy dispersive X-ray spectroscopy due to the interdiffusion. However, the specimens that were sputtered by mixed gases (Ar and $N_2$) exhibited excellent resistance to FCCI. The thickness of these CrN films were only $4{\mu}m$, but these films effectively prevented the FCCI due to their high adhesion strength (frictional force ${\geq}1,200{\mu}m$) and dense columnar microstructures.

GzRUM1, Encoding an Ortholog of Human Retinoblastoma Binding Protein 2, is Required for Ascospore Development in Gibberella zeae

  • Kim, Hee-Kyoung;Lee, Yin-Won;Yun, Sung-Hwan
    • The Plant Pathology Journal
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    • v.27 no.1
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    • pp.20-25
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    • 2011
  • Gibberella zeae (anamorph: Fusarium graminearum), a homothallic (self-ferile) ascomycete with ubiquitous geographic distribution, causes serious diseases in several cereal crops. Ascospores (sexual spores) produced by this fungal pathogen have been suggested as the main source of primary inoculum in disease development. Here, we report the function of a gene designated GzRUM1, which is essential for ascospore formation in G. zeae. The deduced product of GzRUM1 showed significant similarities to the human retinoblastoma (tumor suppressor) binding protein 2 and a transcriptional repressor, Rum1 in the corn smut fungus (Ustilago maydis). The transcript of GzRUM1 was detected during the both vegetative and sexual stages, but was more highly accumulated during the latter stage. In addition, no GzRUM1 transcript was detected in a G. zeae strain lacking a mating-type gene (MAT1-2), a master regulator for sexual development in G. zeae. Targeted deletion of GzRUM1 caused no dramatic changes in several traits except ascospore formation. The ${\Delta}$GzRUM1 strain produced perithecia (sexual fruit bodies) but not asci nor ascospores within them. This specific defect leading to an arrest in ascospore development suggests that GzRUM1, as Rum1 in U. maydis, functions as a transcriptional regulator during sexual reproduction in G. zeae.

Six Sigma and the Cost of(Poor) Quality

  • Aca;U, Jichao-X
    • International Journal of Quality Innovation
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    • v.3 no.2
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    • pp.159-173
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    • 2002
  • Any organization's Six Sigma program may be at high risk without heeding the lessons learned from the past and that tries to operate without a robust business foundation. A foundation that preferably should consist of stepping-stones such as a 5-S house-keeping program, an effective Integrated Management System (IMS), which includes a strong focus on planning for quality to fully capture the Voice of the Customer (VOC), and an organization-wide training scheme, as well as a reliable Cost of Poor Quality (COPQ) system. That's the best advise I can give to any organization that wishes to embark on a Six Sigma improvement program and hope to be successful. The paper will elaborate on the above issues and provide suggested solutions based on the review of published historical information and the experiences encountered over the last four decades by the author, as a quality practitioner and consultant, in industries that produced safety-critical product. This author maintains that few fundamentally new or useful things have been created in the field of Quality during the last couple of decades. Nevertheless, this paper deliberates on a number of relatively “newer” issues including the concept of “three types of customers”, the CTC, “Critical To Customer” term, the eight Quality Management Principles of the new ISO 9000 family, the growth of industry-specific standards, the adoption of Integrated Management Systems, the rebirth of AS2561 COQ standard, the spread of Six Sigma as well as related ASQ certification and the need for a robust business foundation to ensure Six Sigma survival.

Effect of high energy ball milling on the structure of iron - multiwall carbon nanotubes (MWCNT) composite

  • Kumar, Akshay;Pandel, U.;Banerjee, M.K.
    • Advances in materials Research
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    • v.6 no.3
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    • pp.245-255
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    • 2017
  • High energy ball milling is employed to produce iron matrix- multiwall carbon nanotube (MWCNT) reinforced composite. The damage caused to MWCNT due to harsh ball milling condition and its influence on interfacial bonding is studied. Different amount of MWCNT is used to find the optimal percentage of MWCNT for avoidance of the formation of chemical reaction product at the matrix - reinforcement interface. Effect of process control agent is assessed by the use of different materials for the purpose. It is observed that ethanol as a process control agent (PCA) causes degradation of MWCNT reinforcements after milling for two hours whereas solid stearic acid used as process control agent, allows satisfactory conservation of MWCNT structure. It is further noted that at a high MWCNT content (~ 2wt.%), high energy ball milling leads to reaction of iron and carbon and forms iron carbide (cementite) at the iron-MWCNT interface. At low percentage of MWCNT, dissolution of carbon in iron takes place and the amount of reinforcement in iron matrix composite becomes negligibly small. However, under the present ball milling condition (ball to metal ratio~ 6:1 and 200 rpm vial speed) iron-1wt.% MWCNT composite of good interfacial bonding can retain the tubular structure of reinforcing MWCNT.

Merleau-Ponty's Intertwining as a Theory of Communion (교감 이론으로서 메를로퐁티의 '상호 엮임')

  • Kwon, Teckyoung
    • Journal of English Language & Literature
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    • v.57 no.4
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    • pp.581-598
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    • 2011
  • The recent revival of phenomenology and aesthetics is deeply connected to the development of neuroscience which studies the nervous system and the brain with particular regard to cognition and memory. How are those fields gathered into building up the basis for the communication not only between human beings but also between humanity and its environment? This paper examines the human mind considered unseparable from the body, with reference to Merleau-Ponty's two major works: Phenomenology of Perception (1962) and The Visible and the Invisible (1968). While reading these texts, I investigate the way he overturns the Cartesian cogito and establishes the body as the ground of perception. According to him, human perception is chiefly obtained through the body rather than consciousness. Influenced by William James, who produced the unique concept of cognition and memory through his experiments with the brain, Merleau-Ponty extends Heideggerian Desein to the field of the embodied mind. James also anticipates Bergson, who regards memory as the product of interaction between consciousness and matter (or the body). The intervention of the body which stores the past experiences makes it impossible for us to capture the present moment in itself. This failure, however, is viewed as positive by Merleau-Ponty because the human body is not only a medium of social interaction, but also that of ecological communion.

Synthesis and Characterization of Poly(arylene ether)s Containing Benzoxazole Pendants from Novel Aromatic Difluoride Monomer

  • Kim, Ji Hyeong;Bang, Sang U;Kim, Yeong Jun
    • Bulletin of the Korean Chemical Society
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    • v.21 no.9
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    • pp.896-900
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    • 2000
  • A study was done on the synthesis of new poly(arylene ether)s and poly(arylenesulfide) with rigid benzoxazole pendants using nucleophilic aromatic substitution reaction. As a new aromatic monomer, 1,4-bis(2-benzox-azolyl)-2,5-difluorobenzene [I] w as synthesized in three steps starting from 1,4-dibromo-2,5-difluorobenzene. A model reaction of difluoro monomer [I] with two equivalents of m-cresol or thiophenol in a typical ether con-densation reaction conditions gave very high yields ( > 93%) of the desired disubstituted product, suggesting the feasibility of polymer formation in these reaction system. Monomer[I] was polymerized with bisphenols and bisbenzenethiol in NMP using K2CO3 as base. The molecular weight of the resulting polymers, however,seemed relatively low according to their solution viscosity values ( ηinh = 0.15-0.29 dL/g). The poly(arylene ether)s were soluble in several common organic solvents including chloroform, pyridine and N,N'-dimethylfor-mamide. The poly(arylene sulfide) was, however, ony soluble in strong acids like sulfuric acid and trifluoro-acetic acid. The glass transition temperatures were found to be 175-215 $^{\circ}C.$ These polymers were stable up to 380-420 $^{\circ}C$ in both nitrogen and air, as determined by the temperature that a significant weight loss began to appear on TGA.

Survival of Anisakis species larvae of chub mackerel (Scomber japonicus) in different kinds of condiments

  • Nam, U-Hwa;Lee, Seo-Young;Lee, Ji-Hyee;Kim, Jeong-Ho
    • Journal of fish pathology
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    • v.34 no.2
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    • pp.249-253
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    • 2021
  • Anisakiasis is a well-known zoonosis caused by ingestion of raw or thermally undercooked seafood product contaminated with live Anisakis nematode third stage larvae (L3). Several traditional processing techniques have been used to kill or remove the Anisakis larvae worldwide, but thermal processing or deep freezing are the most effective treatments to kill the Anisakis larvae. In this study, we investigated the survival of Anisakis larvae in several condiments (soy bean sauce, wasabi, vinegar, red pepper paste) commonly consumed when eating raw fish in Korea. We also examined several different media (NaCl solution, absolute alcohol, soju) to investigate their larvicidal effect. When directly exposed to various condiments, the most effective larvicidal effect was observed in the mixture of wasabi and soy bean sauce. When exposed to different NaCl solutions, the larvicidal ability became more effective as the concentration increased, but did not show 100% killing effect. In soju, the L3 were killed under less than 4 hr. We observed the larvicidal effects of several condiments in this study, but these results are thought to be carefully interpreted for actual use because all the condiments in this study showed the effect in hours and in general, the L3 are exposed to these condiments only for seconds before ingested in real situation.