• Title/Summary/Keyword: Cross Efficiency

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Computational Drug Discovery Approach Based on Nuclear Factor-κB Pathway Dynamics

  • Nam, Ky-Youb;Oh, Won-Seok;Kim, Chul;Song, Mi-Young;Joung, Jong-Young;Kim, Sun-Young;Park, Jae-Seong;Gang, Sin-Moon;Cho, Young-Uk;No, Kyoung-Tai
    • Bulletin of the Korean Chemical Society
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    • v.32 no.12
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    • pp.4397-4402
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    • 2011
  • The NF-${\kappa}B$ system of transcription factors plays a crucial role in inflammatory diseases, making it an important drug target. We combined quantitative structure activity relationships for predicting the activity of new compounds and quantitative dynamic models for the NF-${\kappa}B$ network with intracellular concentration models. GFA-MLR QSAR analysis was employed to determine the optimal QSAR equation. To validate the predictability of the $IKK{\beta}$ QSAR model for an external set of inhibitors, a set of ordinary differential equations and mass action kinetics were used for modeling the NF-${\kappa}B$ dynamic system. The reaction parameters were obtained from previously reported research. In the IKKb QSAR model, good cross-validated $q^2$ (0.782) and conventional $r^2$ (0.808) values demonstrated the correlation between the descriptors and each of their activities and reliably predicted the $IKK{\beta}$ activities. Using a developed simulation model of the NF-${\kappa}B$ signaling pathway, we demonstrated differences in $I{\kappa}B$ mRNA expression between normal and different inhibitory states. When the inhibition efficiency increased, inhibitor 1 (PS-1145) led to long-term oscillations. The combined computational modeling and NF-${\kappa}B$ dynamic simulations can be used to understand the inhibition mechanisms and thereby result in the design of mechanism-based inhibitors.

Nonlinear Dynamic Analysis of Space Steel Frames (공간 강뼈대 구조물의 비선헝 동적 해석)

  • Kim Seung-Eock;Cuong Ngo-Huu;Lee Dong-Ho
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.18 no.4 s.70
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    • pp.395-404
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    • 2005
  • This paper presents a reliable numerical procedure for nonlinear time-history analysis of space steel frames subjected to dynamic loads. Geometric nonlinearities of member (P-$\delta$) and frame (P-$\Delta$) are taken into account by the use of stability functions in framed stiffness matrix formulation. The gradual yielding along the member length and over the cross section is included by using a tangent modulus concept and a softening plastic hinge model based on the New-Orbison yield surface. A computer program utilizing the average acceleration method for the integration scheme is developed to numerically solve the equation of motion of framed structure formulated in an incremental form. The results of several numerical examples are compared with those derived from using beam element model of ABAQUS program to illustrate the accuracy and the computational efficiency of the proposed procedure.

Risk Assessment of Physical Hazards in Greek Hospitals Combining Staff's Perception, Experts' Evaluation and Objective Measurements

  • Tziaferi, Styliani Gewrgios;Sourtzi, Panayiota;Kalokairinou, Athina;Sgourou, Evi;Koumoulas, Emmanouel;Velonakis, Emmanouel
    • Safety and Health at Work
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    • v.2 no.3
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    • pp.260-272
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    • 2011
  • Objectives: The promotion of health and safety (H&S) awareness among hospital staff can be applied through various methods. The aim of this study was to assess the risk level of physical hazards in the hospital sector by combining workers' perception, experts' evaluation and objective measurements. Methods: A cross-sectional study was designed using multiple triangulation. Hospital staff (n = 447) filled in an H&S questionnaire in a general hospital in Athens and an oncology one in Thessaloniki. Experts observed and filled in a checklist on H&S in the various departments of the two hospitals. Lighting, noise and microclimate measurements were performed. Results: The staff's perception of risk was higher than that of the experts in many cases. The measured risk levels were low to medium. In cases of high-risk noise and lighting, staff and experts agreed. Staff's perception of risk was influenced by hospital's department, hospital's service, years of working experience and level of education. Therefore, these factors should be taken into account in future studies aimed at increasing the participation of hospital workers. Conclusion: This study confirmed the usefulness of staff participation in the risk assessment process, despite the tendency for staff to overestimate the risk level of physical hazards. The combination of combining staff perception, experts' evaluation and objective measures in the risk assessment process increases the efficiency of risk management in the hospital environment and the enforcement of relevant legislation.

A Diamond Web-grid Search Algorithm Combined with Efficient Stationary Block Skip Method for H.264/AVC Motion Estimation (H.264/AVC 움직임 추정을 위한 효율적인 정적 블록 스킵 방법과 결합된 다이아몬드 웹 격자 탐색 알고리즘)

  • Jeong, Chang-Uk;Choi, Jin-Ku;Ikenaga, Takeshi;Goto, Satoshi
    • Journal of Internet Computing and Services
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    • v.11 no.2
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    • pp.49-60
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    • 2010
  • H.264/AVC offers a better encoding efficiency than conventional video standards by adopting many new encoding techniques. However, the advanced coding techniques also add to the overall complexity for H.264/AVC encoder. Accordingly, it is necessary to perform optimization to alleviate the level of complexity for the video encoder. The amount of computation for motion estimation is of particular importance. In this paper, we propose a diamond web-grid search algorithm combined with efficient stationary block skip method which employs full diamond and dodecagon search patterns, and the variable thresholds are used for performing an effective skip of stationary blocks. The experimental results indicate that the proposed technique reduces the computations of the unsymmetrical-cross multi-hexagon-grid search algorithm by up to 12% while maintaining a similar PSNR performance.

Analysis of Relative Importance of Socio·Economic Factors in Establishing Diagnosis Systems for Impaired Stream Ecosystem (국내 수생태계 훼손 원인 진단체계 구축을 위한 사회·경제적 특성의 상대적 중요도 분석)

  • An, Kyung-Jin;Kim, Su-Yeon;Lee, Sang-Woo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.21 no.2
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    • pp.13-26
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    • 2018
  • The restoration of the impaired stream ecosystem is an important part of river policies in Ministry of Environment (MoE). However, the diagnosing the impairment sources of stream ecosystem has been omitted on the current river projects and policies. This phenomena lead the remaining impairment sources keep influencing on negative effects on streams. Hence, it is critical to construct a diagnosis system of impairment sources in order to increase the efficiency of various river restoration projects and policies. Moreover, it is also important to understand the relative impact of socio-economic factors of the impairment of stream ecosystems so as to build a domestic diagnosis system in place. Therefore, the study aims to analyse the relative effects of socio-economic factors which are the source of the stream ecosystem impairments through implementing the Analytic Hierarchy Process (AHP). In order to achieve the goal, a list of socio-economic factors influencing the stream health has been derived. On the basis of the derived causes list, AHP questionnaire were carried out to the experts of aquatic ecology. The study results could be implemented to analysing the relative influence of socio-economic impairment causes in domestic stream environments. In addition, more case study investigation is needed to cross-check if the derived impairment causes and weights are applied in the field as well as to develop more reliable indicators.

Comparison of Lines from Anther and Maternally-derived Dihaploids in Flue-cured Tobacco(Nicotiana tabacum L.) (황색종 연초의 약배양 및 종간교배에 의한 반수체 배가계통의 특성비교)

  • Jeong, Yun-Hwa;Lee, S. C.;Kim, D. U.
    • Journal of the Korean Society of Tobacco Science
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    • v.14 no.1
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    • pp.24-32
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    • 1992
  • The present study was conducted to compare the relative efficiency of two different haploid breeding methods in tobacco varietal development. A single F t hybrid plant from cross of two flue-cured cultivars of Nicotiana tabacum L., Bright Yellow4(BY4) and NC 95, was used to develop the 30 dihaploid lines by anther culture(F1-ADH) and maternally-derived doubled haploid utilizing Nicotiana africana(F1-MDH), respectively. As compared with mid-parent, ADH lines showed increasing in number of leaves, delaying in days to flower and narrowing in leaf width. However, no significant differences in the other characters investigated were recognized. MDH lines also showed narrow leaf width, while no significant differences in the other characters were observed. The variations of the characters investigated were generally greater in ADH than MDH lines. MDH lines had higher plant height and shorter days to flower than ADH lines, while other characters did not show remarkable differences. The degree of heritability for each of the characters observed between ADH and MDH was almost the same. The characters showing high heritability value were plant height, leaf number, days to flower, and yield, while those showing relatively low value were leaf length, leaf width, and total alkaloid content. Predicted gains from selection for increased yield were calculated for both populations(F1-ADH, F1-MDH) and correlated responses associated with selection for yield were estimated. Plant height, leaf width, days to flower, percent reducing sugar and disease resistance would be expected to improve with selection for yield much faster in the MDH population than in the ADH.

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Effect of growth interruption on InN/GaN single quantum well structures

  • Kwon, S.Y.;Kim, H.J.;Na, H.;Seo, H.C.;Kim, H.J.;Shin, Y.;Kim, Y.W.;Yoon, S.;Oh, H.J.;Sone, C.;Park, Y.;Sun, Y.P.;Cho, Y.H;Cheong, H.M.;Yoon, E.
    • Journal of the Korean Vacuum Society
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    • v.12 no.S1
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    • pp.95-99
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    • 2003
  • We successfully grew InN/GaN single quantum well structures by metal-organic chemical vapor deposition and confirmed their formation by optical and structural measurements. We speculate that relatively high growth temperature ($730^{\circ}C$) of InN layer enhanced the formation of 2-dimensional quantum well structures, presumably due to high adatom mobility. As the growth interruption time increased, the PL emission efficiency from InN layer improved with peak position blue-shifted and the dislocation density decreased by one order of magnitude. The high resolution cross-sectional TEM images clearly showed that the InN layer thickness reduced from 2.5 nm (without GI) to about I urn (with 10 sec GI) and the InN/GaN interface became very flat with 10 sec GI. We suggest that decomposition and mass transport processes on InN during GI is responsible for these phenomena.

Compact Cascaded Quadruplet Bandpass Filter Using Modified Coaxial Cavity Resonator with Q-Factor Improvement (품질계수가 향상된 변형된 동축 공동 공진기를 이용한 다단 Quadruplet 대역통과 여파기)

  • Jang, Geon-Ho;Wang, Xu-Guang;Lee, Bo-Ram;Park, Nam-Shin
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.26 no.11
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    • pp.966-977
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    • 2015
  • This paper presents a novel modified coaxial cavity resonator and its application to bandpass filters with compact size and improved quality factor(Q-factor). The proposed resonator is made up of ${\Gamma}-shape$ or curved four inner conductive posts within a single cavity, which provides quadruplet to realize bandpass filter. No metallic walls inside the cavity are required, and thus the utilization efficiency of the cavity space is improved. As a result, the unloaded Q can be approximately 15 % higher in comparison to the conventional coaxial resonator, or more than 35 % volume saving can be achieved while maintaining the similar Q-factor value with the conventional designs. In addition, due to the multiple cross-coupling occurring within the cavity, including the source-to-load coupling, four flexible transmission zeros can be created to realize different filtering functions. Simulations as well as experimental results of four- and eight-pole filters are presented to validate this attractive design concept. Good agreement between measured and computed results is obtained.

Evaluation on the Performance of Nursing in according to the Nursing grade of Hospitals (병원 간호등급에 따른 간호수행 정도)

  • Yun, Soon-Gil;Park, Jae-Yong;Kim, Key-Hoon;Han, Chang-Hyun
    • Korea Journal of Hospital Management
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    • v.15 no.3
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    • pp.1-16
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    • 2010
  • As a cross-sectional study, this study was aimed to investigate and compare the job efficiency and satisfaction of nurses according to the hospital grade. Survey was conducted by mail on June 2009, and the respondents were 1,016 nurses working in 15 hospitals which are 9 high-grade general hospitals and 6 general hospitals. The percent of nurses acknowledging their hospital grades is 34.5%, and that is 20.5% at high-grade general hospitals. As the result of review of studies, it is concluded that under the circumstance that differential rates are contracted to calculate fees for hospital services and copayment of patients are according to nursing grades and hospital grades, the degree of nurses' awareness of insurance fees impact on their performance like recording of care and prescription. In order to improve nurses' performance, they need to be educated about the national insurance fee system. In hospitals with higher nursing grade and more beds, the levels of nursing quality and faithfulnes and their job satisfaction were higher. Nurses' awareness of their hospital nursing grade was related to the quality of nursing but not the faithfulness. Nurses working in higher nursing-grade hospital are more self-respect and satisfied at their jobs, and their job efficiencies are not significantly different. The current nursing fees based on the proper number of nurses per beds of nursing units should be changed to be based on the amount of job per nurse by their nursing protocol, and the nurse staffing standard should be differentiated between nursing grades. As the aspect of nursing, 24-hours patient care, it is difficult to improve nurses' job satisfaction, and in the other hand, that tends to depend on their income level. In the current circumstance, comprehensive research is required to investigate the propriety of 25% of the inpatient fees as the nursing management charge.

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Numerical Analysis of Steam-methane Reforming Reaction for Hydrogen Generation using Catalytic Combustion (촉매 연소를 열원으로 한 수증기-메탄개질반응 전산유체해석)

  • Lee, Jeongseop;Lee, Kanghoon;Yu, Sangseok;Ahn, Kookyoung;Kang, Sanggyu
    • Transactions of the Korean hydrogen and new energy society
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    • v.24 no.2
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    • pp.113-120
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    • 2013
  • A steam reformer is a chemical reactor to produce high purity hydrogen from fossil fuel. In the steam reformer, since endothermic steam reforming is heated by exothermic combustion of fossil fuel, the heat transfer between two reaction zones dominates conversion of fossil fuel to hydrogen. Steam Reforming is complex chemical reaction, mass and heat transfer due to the exothermic methane/air combustion reaction and the endothermic steam reforming reaction. Typically, a steam reformer employs burner to supply appropriate heat for endothermic steam reforming reaction which reduces system efficiency. In this study, the heat of steam reforming reaction is provided by anode-off gas combustion of stationary fuel cell. This paper presents a optimization of heat transfer effect and average temperature of cross-section using two-dimensional models of a coaxial cylindrical reactor, and analysis three-dimensional models of a coaxial cylindrical steam reformer with chemical reaction. Numerical analysis needs to dominant chemical reaction that are assumed as a Steam Reforming (SR) reaction, a Water-Gas Shift (WGS) reaction, and a Direct Steam Reforming(DSR) reaction. The major parameters of analysis are temperature, fuel conversion and heat flux in the coaxial reactor.