• Title/Summary/Keyword: Aggregate Distribution

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The treatment of coal fly ash for the recycling as ceramic raw materials : I. The effect of calcination and elutriation (요업원료로 재활용하기 위한 석탄회의 처리 : I. 하소 및 수비의 영향)

  • 김유택;이준호;정철원;허화범;신건철
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.5 no.4
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    • pp.414-422
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    • 1995
  • Coal fly ash was calcined and elutriated for recycling as ceramic raw materials. C Crystal phases, morphologies, chemical components, particle size distributions and Ig. loss of as-received, calcined and elutriated coal fly ash were investigated to study the effects of the calci nation and elutriation on the coal fly ash classification. The experimental equations, which were used in elutriation of clay, were examined in order to find out which equation is appropriated for coal fly ash classification. It turned out that Rittinger's equation is relatively well matched for the fly ash. Having nothing to do with the treatment conditions, the crystal phases of coal f fly ash were mullite, quartz. Calcite peak was detected in as - received and elutriated coal fly a ash; however, it disappeared in calcined coal fly ash. As - received coal fly ash consists of various type of particles such as a cenosphere, coke type, silicate type, whisker type and aggregat e ed type. In case of calcined coal fly ash, coke type particles were eliminated and agglomerated type particles were relatively increased. Most of the particles that were relatively spherical cenosphere in the 4th step of elutriator. Particle size distribution was narrowed by calcination a and elutriation. Especially, in elutriation, particle size distribution was very narrow.

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Distributional Characteristics and Improvements for Wildlife Protection Areas in South Korea (야생동·식물보호구역 분포 특성과 개선과제)

  • Lee, Gwan-Gyu
    • Journal of Environmental Impact Assessment
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    • v.20 no.5
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    • pp.685-695
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    • 2011
  • Through the analyses of the distribution characteristics and management practices of the wildlife protection areas, this study intends to present basic data for improving the management of protected areas. 1) Based on the aggregate results of the protected areas, the average ratio of the metro-city and provincial areas to the designated protected areas was 1.49%; except for Chungcheongbuk-do (8.83%) and Gyeongsangnam-do (3.43%), most regions showed specified percentages of about 1%, whereby the analysis suggested that the designated protected areas were too small. 2) Considering the fact that most (86.16%) of the wildlife protection areas are in the regions that are of ecological nature level of grade 1, green nature level of grade 8 or better, and of legal conservation regions and districts, it was shown that these reserves are distributed in regions with excellent natural environmental conditions. 3) Designation of protected areas for the protection of wildlife and fish is deemed to be necessary. Although there are 588 wildlife & plant reserves, there are absolutely no designated areas for protecting plant and fish species. 4) Based on the results of an analysis of the current distribution by types, 92.47% of protected areas were concentrated in the mountains, 0.24% in the agricultural lands, and 7.29% distributed in the lakes/rivers/costal areas. 5) As major improvement projects, proposed were: advancement of management systems for protected areas, expanded designation of protected areas, overhaul of managed areas, designation of protected areas for the protection of wild plants and fish, need for management measures for private property and the surrounding areas, need to secure appropriate management personnel and collaboration, locally-adapted management, eco-information-based management, total management of protected areas, etc.

A Stochastic Bilevel Scheduling Model for the Determination of the Load Shifting and Curtailment in Demand Response Programs

  • Rad, Ali Shayegan;Zangeneh, Ali
    • Journal of Electrical Engineering and Technology
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    • v.13 no.3
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    • pp.1069-1078
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    • 2018
  • Demand response (DR) programs give opportunity to consumers to manage their electricity bills. Besides, distribution system operator (DSO) is interested in using DR programs to obtain technical and economic benefits for distribution network. Since small consumers have difficulties to individually take part in the electricity market, an entity named demand response provider (DRP) has been recently defined to aggregate the DR of small consumers. However, implementing DR programs face challenges to fairly allocate benefits and payments between DRP and DSO. This paper presents a procedure for modeling the interaction between DRP and DSO based on a bilevel programming model. Both DSO and DRP behave from their own viewpoint with different objective functions. On the one hand, DRP bids the potential of DR programs, which are load shifting and load curtailment, to maximize its expected profit and on the other hand, DSO purchases electric power from either the electricity market or DRP to supply its consumers by minimizing its overall cost. In the proposed bilevel programming approach, the upper level problem represents the DRP decisions, while the lower level problem represents the DSO behavior. The obtained bilevel programming problem (BPP) is converted into a single level optimizing problem using its Karush-Kuhn-Tucker (KKT) optimality conditions. Furthermore, point estimate method (PEM) is employed to model the uncertainties of the power demands and the electricity market prices. The efficiency of the presented model is verified through the case studies and analysis of the obtained results.

Computer Simulation of Hemispherical Sheet Forming Process Using Crystal Plasticity (결정 소성학을 이용한 반구 박판 성형공정 전산모사)

  • Shim, J.G.;Keum, Y.T.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2007.05a
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    • pp.282-284
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    • 2007
  • The hardening and the constitutive equation based on the crystal plasticity are introduced for the numerical simulation of hemispherical sheet metal forming. For calculating the deformation and the stress of the crystal, Taylor's model of the crystalline aggregate is employed. The hardening is evaluated by using the Taylor factor, the critical resolved shear stress of the slip system, and the sum of the crystallographic shears. During the hemispherical forming process, the texture of the sheet metal is evolved by the plastic deformation of the crystal. By observing the texture evolution of the BCC sheet, the texture evolution of the sheet is traced during the forming process. Deformation texture of the BCC sheet is represented by using the pole figure. The comparison of the strain distribution and punch force in the hemispherical forming process between crystal plasticity and experiment shows the verification of the crystal-based formulation and the accuracy of the hardening and constitutive equation obtained from the crystal plasticity.

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Nexus between Indian Economic Growth and Financial Development: A Non-Linear ARDL Approach

  • KUMAR, Kundan;PARAMANIK, Rajendra Narayan
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.6
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    • pp.109-116
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    • 2020
  • The study examines the nexus between financial development and economic growth in India during Q1: 1996 to Q3: 2018. This study employs time-series data of real GDP and ratio of broad money to GDP as a proxy for economic and financial development, respectively. The data are obtained from RBI database on the Indian economy. All variables are seasonally adjusted using X12-arima technique and expressed in natural logarithm form. Non-linear Autoregressive Distributed Lag (NARDL) bound test has been used to check for cointegrating relationship of these two variables. Empirical findings suggest that, unlike in the short run, in the long run financial development does impact economic growth positively. Further, a symmetric effect of positive and negative components of financial development is found for the Indian economy, whereas the effect of control variable like exchange rate and trade openness is in consonance with common economic intuition. Exchange rate is in consonance with intuitive economic logic that a fall in exchange rate makes exports cheaper and increases the quantity of export, which improves the balance of payment and leads to a rise in aggregate demand, hence improves economic growth. This paper contributes to the existing literature on India by breaking down financial indicator into positive and negative components to examine the finance-growth relationship.

Executive Compensation in Korea: Evidence from a New Mandatory Disclosure

  • GWON, Jae Hyun;MOON, Byoung Soon
    • The Journal of Asian Finance, Economics and Business
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    • v.6 no.3
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    • pp.91-101
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    • 2019
  • This paper finds some stylized facts about executive pay in South Korea. Using aggregate data of the listed companies since 2002, we find that 1) the director's remuneration has risen faster than the employee compensation, thus, the pay ratio of executive and employee has escalated from 3.0 to 4.5; 2) the executive compensation for large business group fluctuates more widely than that for small and medium enterprises does, hence the pay ratio for large firms changes widely too; 3) the median pay ratio has not grown monotonically but it rather rises to remain still around year 2011, which is accounted for mostly by small and medium enterprises. New information on executive compensation by compulsory disclosure starting from 2013 made further analysis of CEO compensation attainable. Based on the conventional regression analysis for 2013-2017, we find that 1) the elasticity of CEO pay with respect to firm value is about 0.18; 2) the volatility of stock return is negatively related to CEO pay; 3) contemporaneous stock return is positively associated with the pay; 4) there is insufficient evidence that large business groups pay their CEOs more than small and medium enterprises do. These results are robust under various model specifications.

Mass Spectrometric Study of Carbon Cluster Formation in Laser Ablation of Graphite at 355 nm

  • Koo, Young-Mi;Choi, Young-Ku;Lee, Kee-Hag;Jung, Kwang-Woo
    • Bulletin of the Korean Chemical Society
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    • v.23 no.2
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    • pp.309-314
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    • 2002
  • The ablation dynamics and cluster formation of $C_n^+$ ions ejected from 355 nm laser ablation of a graphite target in vacuum are investigated using a reflectron time-of-flight (RTOF) mass spectrometer. At low laser fluence, odd-numbered cluster ions with $3{\leq}n{\leq}15$ are predominantly produced. Increasing the laser fluence shifts the maximum size distribution towards small cluster ions, implying the fragmentation of larger clusters within the hot plume. The temporal evolution of $C_n^+$ ions was measured by varying the delay time of the ion extraction pulse with respect to the laser irradiation, providing significant information on the characteristics of the ablated plume. Above a laser fluence of $0.2J/cm^2$ , large cluster ions ($n{\geq}30$) are produced at relatively long delay times, indicating that atoms or small carbon clusters aggregate during plume propagation. The dependence of the intensity of ablated $C_n^+$ ions on delay time after laser irradiation shows that the most probable velocity of each cluster ion decreases with cluster size.

Performance Evaluation of Multimodal Biometric System for Normalization Methods and Classifiers (균등화 및 분류기에 따른 다중 생체 인식 시스템의 성능 평가)

  • Go, Hyoun-Ju;Woo, Na-Young;Shin, Yong-Nyuo;Kim, Jae-Sung;Kim, Hak-Il;Chun, Myung-Geun
    • Journal of KIISE:Software and Applications
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    • v.34 no.4
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    • pp.377-388
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    • 2007
  • In this paper, we propose a multi-modal biometric system based on face, iris and fingerprint recognition system. To effectively aggregate two systems, we use statistical distribution models based on matching values for genuine and impostor, respectively. And then, We performed reveal fusion algorithms including weighted summation, Support Vector Machine(SVM), Fisher discriminant analysis, Bayesian classifier. From the various experiments, we found that the performance of multi-modal biometric system was influenced with the normalization methods and classifiers.

Relationship between Accrual Anomaly and Stock Return: The Case of Vietnam

  • DANG, Hung Ngoc;TRAN, Dung Manh
    • The Journal of Asian Finance, Economics and Business
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    • v.6 no.4
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    • pp.19-26
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    • 2019
  • The study investigates the impact of accrual anomaly on stock return ratio of listed firms in Vietnam. Data were collected from listed firms for the period from 2008 to 2018. To learn about the causes of accrual anomaly in returns and future rate of returns on the Vietnamese stock market, this research is based on accrual analysis of Richardson, Sloan, Soliman, and Tuna (2006) on growth and effective components. We employ GLS regression model for examining the impact of accrual anomaly on stock return ratio and T-test for checking the difference between the lowest and the highest portfolio. The results show that accounting distortion is the main factor impacting the stock return, not growth determinant. Both two determinants of accounting distortion and growth contribute the explanation of the impact of accrual anomaly on profit and future stock return ratio. Experimental evidence confirms an abnormal existence of accrual in the Vietnam stock market. Aggregate accrual is negatively correlated with future operating profit and future stock return. However, after considering the factors contributing to the impact of future profitability and return on stock returns, the study results show that accounting distortion can account for low sustainability of income that is not growth.

Looking at Organizational Socialization from the Developmental Network Perspective

  • Chang, Jihyun;Kim, Taesung
    • The Journal of Asian Finance, Economics and Business
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    • v.5 no.3
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    • pp.195-206
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    • 2018
  • Paying close attention to those new to an organization, whether fresh or experienced, whose primary interest is in (re)socialization, the current study intends to (1) further the concept of mentoring from a bilateral relationship to a community and culture fostered by developmental networks, (2) propose an integrated conceptual framework for organizational socialization, and (3) suggest implications for practice and future research. This study reviews, analyzes, and integrates research assets and subsequently re-conceptualizes the aggregate information as valid propositions and a conceptual framework. The findings include (1) 11 propositions regarding the relationships among network characteristics (embeddedness, diversity), developmental functions (career support, psychosocial support, and role modeling), and socialization outcomes (learning and attitudinal outcomes); and (2) an integrated conceptual framework that depicts a comprehensive mechanism through which developmental networks conduce to organizational socialization of newcomers. Implications are that developmental networking must be an individual's fundamental competency and an essential part of organizational onboarding processes, and imperative for both members' career development and innovative organizational culture. By integrating research assets on the developmental phenomenon into conceptualizations, this study furthers the concept of mentoring to organizational culture and stimulates a substantive discourse for theory-building towards organizational socialization from the developmental network perspective.