• Title/Summary/Keyword: Quantitative expansion

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A Study on Impact of Generator Maintenance Outage Modeling on Long-term Capacity Expansion Planning (발전기 계획예방정비 모델링 방식이 전원계획 수립에 미치는 영향에 관한 연구)

  • Kim, Hyoungtae;Lee, Sungwoo;Kim, Wook
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.4
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    • pp.505-511
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    • 2018
  • Long term capacity expansion planning has to be carried out to satisfy pre-defined system reliability criterion. For purpose of assessing system reliability, probabilistic simulation technique has been widely adopted. However, the way how to approximate generator outage, especially maintenance outage, in probabilistic simulation scheme can significantly influence on reliability assessment. Therefore, in this paper, 3 different maintenance approximation methods are applied to investigate the quantitative impact of maintenance approximation method on long term capacity expansion planning.

Asymmetric Effects of Global Liquidity Expansion on Foreign Portfolio Inflows, Exchange Rates, and Stock Prices

  • Rhee, Dong-Eun;Yang, Da Young
    • East Asian Economic Review
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    • v.18 no.2
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    • pp.143-161
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    • 2014
  • This paper examines the effects of global liquidity expansion on advanced and emerging economies by using panel VAR methodology. The results show that global liquidity expansion tends to boost economy by increasing GDP growth and stock prices. However, we find that the effects are asymmetric. The effects of global liquidity on GDP and stock prices are greater and more persistent in emerging economies than in liquidity recipient advanced economies. Moreover, global liquidity appreciates emerging economies' exchange rates more persistently than those of advanced economies. Lastly, while global liquidity expansion increases foreign portfolio investment inflows to Asian countries and liquidity recipient advanced economies, there is no evidence for Latin American countries.

Effectiveness of miniscrew assisted rapid palatal expansion using cone beam computed tomography: A systematic review and meta-analysis

  • Siddhisaributr, Patchaya;Khlongwanitchakul, Kornkanok;Anuwongnukroh, Niwat;Manopatanakul, Somchai;Viwattanatipa, Nita
    • The korean journal of orthodontics
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    • v.52 no.3
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    • pp.182-200
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    • 2022
  • Objective: This study aims to examine the effectiveness of miniscrew assisted rapid palatal expansion (MARPE) treatment in late adolescents and adult patients using cone-beam computed tomography (CBCT). Methods: Literature search was conducted in five electronic databases (PubMed, Embase, Scopus, Web of Science, and Cochrane Library) based on the PICOS keyword design focusing on MARPE. Out of the 18 CBCT screened outcomes, only nine parameters were sufficient for the quantitative meta-analysis. The parameters were classified into three main groups: 1) skeletal changes, 2) alveolar change, and 3) dental changes. Heterogeneity test, estimation of pooled means, publication bias, sensitivity analysis and risk of bias assessment were also performed. Results: Upon database searching, only 14 full-text articles were qualified from the 364 obtained results. Heterogeneity test indicated the use of the random-effects model. The pooled mean estimate were as follows: 1) Skeletal expansion: zygomatic width, 2.39 mm; nasal width, 2.68 mm; jugular width, 3.12 mm; and midpalatal suture at the posterior nasal spine and anterior nasal spine, 3.34 mm and 4.56 mm, respectively; 2) Alveolar molar width expansion, 4.80 mm; and 3) Dental expansion: inter-canine width, 3.96 mm; inter-premolar width, 4.99 mm and inter-molar width, 5.99 mm. The percentage of expansion demonstrated a skeletal expansion (PNS) of 55.76%, alveolar molar width expansion of 24.37% and dental expansion of 19.87%. Conclusions: In the coronal view, the skeletal and dental expansion created by MARPE was of the pyramidal pattern. MARPE could successfully expand the constricted maxilla in late adolescents and adult patients.

Comparative Study of Contrast-Enhanced Ultrasound Qualitative and Quantitative Analysis for Identifying Benign and Malignant Breast Tumor Lumps

  • Liu, Jian;Gao, Yun-Hua;Li, Ding-Dong;Gao, Yan-Chun;Hou, Ling-Mi;Xie, Ting
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.19
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    • pp.8149-8153
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    • 2014
  • Background: To compare the value of contrast-enhanced ultrasound (CEUS) qualitative and quantitative analysis in the identification of breast tumor lumps. Materials and Methods: Qualitative and quantitative indicators of CEUS for 73 cases of breast tumor lumps were retrospectively analyzed by univariate and multivariate approaches. Logistic regression was applied and ROC curves were drawn for evaluation and comparison. Results: The CEUS qualitative indicator-generated regression equation contained three indicators, namely enhanced homogeneity, diameter line expansion and peak intensity grading, which demonstrated prediction accuracy for benign and malignant breast tumor lumps of 91.8%; the quantitative indicator-generated regression equation only contained one indicator, namely the relative peak intensity, and its prediction accuracy was 61.5%. The corresponding areas under the ROC curve for qualitative and quantitative analyses were 91.3% and 75.7%, respectively, which exhibited a statistically significant difference by the Z test (P<0.05). Conclusions: The ability of CEUS qualitative analysis to identify breast tumor lumps is better than with quantitative analysis.

AHP-Based Evaluation Model for Optimal Selection Process of Patching Materials for Concrete Repair: Focused on Quantitative Requirements

  • Do, Jeong-Yun;Kim, Doo-Kie
    • International Journal of Concrete Structures and Materials
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    • v.6 no.2
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    • pp.87-100
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    • 2012
  • The process of selecting a repair material is a typical one of multi-criteria decision-making (MCDM) problems. In this study Analytical Hierarch Process was applied to solve this MCDM problem. Many factors affecting a process to select an optimal repair material can be classified into quantitative and qualitative requirements and this study handled only quantitative items. Quantitative requirements in the optimal selection model for repair material were divided into two parts, namely, the required chemical performance and the required physical performance. The former is composed of alkali-resistance, chloride permeability and electrical resistivity. The latter is composed of compressive strength, tensile strength, adhesive strength, drying shrinkage, elasticity and thermal expansion. The result of the study shows that this method is the useful and rational engineering approach in the problem concerning the selection of one out of many candidate repair materials even if this study was limited to repair material only for chloride-deteriorated concrete.

Development of an Integrated Evaluation Method for National Protected Areas Based on Aichi Biodiversity Target 11 (아이치 생물다양성 목표 11에 기초한 국가 보호지역의 통합 평가 체계 개발)

  • Hong, Jin-Pyo;Shim, Yun-Jin
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.21 no.1
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    • pp.83-94
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    • 2018
  • This study presents an integrated evaluation method to assess the level of achievement of quantitative expansion goals and qualitative improvement goals based on the Aichi Biodiversity Target 11 for quantitatively expanding and qualitatively improving national protected areas. The quantitative evaluation indicators for national protected areas are the percentage of terrestrial and inland water areas protected and the percentage of marine and coastal areas protected. The quantitative evaluation indicators for national protected areas are selected as 6 indicators: 1) ecologically important areas, 2) ecological representativeness, 3) management effectiveness, 4) connectivity, 5) social equity and 6) integration. Ecologically important areas are an indicator which evaluates how many areas of particular importance for biodiversity and ecosystem services are included in national protected areas. Ecological representativeness is to assess how well national protected areas represent the ecosystem. Management effectiveness is an indicator which evaluates how effectively national protected areas are conserved and managed, and connectivity is an indicator to assess how well national protected areas are connected. Social equity is evaluating how equitably national protected areas are managed and the integration is assessing how much national protected areas are integrated into the wilder landscape and seascape. This study is significant in that it provides a perspective of qualitative improvement as well as quantitative expansion of national protected areas for biodiversity conservation through accurately understanding Aichi Biodiversity Target 11.

Analysis of Window Thermal Performance according to Guidelines on the Balcony Expansion Costs (발코니 확장비용 가이드라인에 따른 창호 열성능 분석)

  • Choi, Gyoung-Seok;Kang, Jae-Sik;Lee, Seung-Eon
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.863-868
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    • 2008
  • In accordance with the guidelines on the balcony structure changes in December 2005, most of tenants were moving into apartment housing, expand the balcony, but some large deviation between the price construction costs set of cases, due to overuse and the cause of the dispute, and the housing law amended in 2007 due to price cap system is implemented, the cost of expansion the balcony overdose pointed out that there is set to boost the sale price has been raised. These issues in order to improve the government in January 2008, the "Note costs by the balcony expansion" suggested guidelines to protect the rights of tenants and wants to promote the settlement of the sale price cap system. This study calculated the "Note costs by the balcony expansion" window system based on double or single, high performance insulation window system of the quantitative performance analysis of each type window that purpose.

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Influences of Process Conditions on the Surface Expansion and Contact Pressure in Backward Can Extrusion of Al Alloys (알루미늄 합금을 이용한 후방압출에 의한 캔 성형시 성형 조건이 표면확장과 접촉 압력에 미치는 영향)

  • Min, K.H.;Seo, J.M.;Koo, H.S.;Vishara, R.J.;Tak, S.H.;Lee, I.C.;Hwang, B.B.
    • Transactions of Materials Processing
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    • v.16 no.7
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    • pp.521-529
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    • 2007
  • This paper is concerned with the analysis on the surface expansion of AA 2024 and AA 1100 aluminum alloys in backward extrusion process. Due to heavy surface expansion appeared usually in the backward can extrusion process, the tribological conditions along the interface between the material and the punch land are very severe. In the present study, the surface expansion is analyzed especially under various process conditions. The main goal of this study is to investigate the influence of degree of reduction in height, geometries of punch nose, friction and hardening characteristics of different aluminum alloys on the material flow and thus on the surface expansion on the working material. Two different materials are selected for investigation as model materials and they are AA 2024 and AA 1100 aluminum alloys. The geometrical parameters employed in analysis include punch corner radius and punch nose angle. The geometry of punch follows basically the recommendation of ICFG and some variations of punch geometry are adopted to obtain quantitative information on the effect of geometrical parameters on material flow. Extensive simulation has been conducted by applying the rigid-plastic finite element method to the backward can extrusion process under different geometrical, material, and interface conditions. The simulation results are summarized in terms of surface expansion at different reduction in height, deformation patterns including pressure distributions along the interface between workpiece and punch, comparison of surface expansion between two model materials, geometrical and interfacial parametric effects on surface expansion, and load-stroke relationships.

A Study on the Profile Change Measurement of Steam Generator Tubes with Tube Expansion Methods

  • Kim, Young-Kyu;Song, Myung-Ho;Choi, Myung-Sik
    • Journal of the Korean Society for Nondestructive Testing
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    • v.31 no.5
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    • pp.543-551
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    • 2011
  • Steam generator tubes for nuclear power plants contain the local shape transitions on their inner or outer surface such as dent, bulge, over-expansion, eccentricity, deflection, and so on by the application of physical force during the tube manufacturing and steam generator assembling and by the sludge (that is, corrosion products) produced during the plant operation. The structural integrity of tubes will be degraded by generating the corrosive crack at that location. The profilometry using the traditional bobbin probes which are currently applied for measuring the profile change of tubes gives us basic information such as axial locations and average magnitudes of deformations. However, the three-dimensional quantitative evaluation on circumferential locations, distributional angle, and size of deformations will have to be conducted to understand the effects of residual stresses increased by local deformations on corrosive cracking of tubes. Steam generator tubes of Korean standard nuclear power plants expanded within their tube-sheets by the explosive expansion method and suffered from corrosive cracks in the early stage of power operation. Thus, local deformations of steam generator tubes at the top of tube-sheet were measured with an advanced rotating probe and a laser profiling system for the two cases where the tubes expanded by the explosive expansion method and hydraulic expansion. Also, the trends of eccentricity, deflection, and over-expansion of tubes were evaluated. The advanced eddy current profilometry was confirmed to provide accurate information of local deformations compared with laser profilometry.

CHANCES OF THE NASAL AIRWAY RESISTANCE WITH RAPID PALATAL EXPANSION USING RHINOMANOMETRY (상악골 급속 확장시(Rapid Palatal Expansion) 비강통기도 검사(Rhinomanometry)를 통한 비강기도 저항(Nasal Airway Resistance) 변화에 관한 연구)

  • Baik, Hyoung-Seon;Koh, Sung-Hui;Lee, Jeung-Gweon
    • The korean journal of orthodontics
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    • v.21 no.1 s.33
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    • pp.17-29
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    • 1991
  • The purpose of this study was to provide quantitative data describing the effect of rapid palatal expansion (RPE) on nasal airway resistance (NAR). RPE is an orthopedic procedure which is commonly used to widen the maxilla in skeletal Class III patients. 18 subjects (9 males and 9 females, mean age: 10 years 7 months) were selected from the Orthodontics in Yongdong Severance Hospital. Recordings of NAR were taken by active anterior method prior to expansion, immediately after desired maximum expansion, and after approximately 3 months and 6 months, and 1 year. All data was recorded and statistically processed with the SPSS program of IBM PC system. The results are as followings . 1. The average initial NAR of the subjects was 3.84 cm $H_2O/LPS\;(SD{\pm}1.34)$. It was greater than the average NAR of the normal subjects. 2. Among 18 subjects, 9 subjects showed reduction of NAR and 9 subjects showed no specific change of NAR after expansion. 3 An average reduction in NAR after immediately expansion was statistically significant at the 0.05 level. 4. The reduction appeared stable throughout the post treatment observation period of 1 year after expansion. From these results, it was suggested that RPE is a useful method to reduce NAR.

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