• Title/Summary/Keyword: volumes

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Integer-Valued HAR(p) model with Poisson distribution for forecasting IPO volumes

  • SeongMin Yu;Eunju Hwang
    • Communications for Statistical Applications and Methods
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    • v.30 no.3
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    • pp.273-289
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    • 2023
  • In this paper, we develop a new time series model for predicting IPO (initial public offering) data with non-negative integer value. The proposed model is based on integer-valued autoregressive (INAR) model with a Poisson thinning operator. Just as the heterogeneous autoregressive (HAR) model with daily, weekly and monthly averages in a form of cascade, the integer-valued heterogeneous autoregressive (INHAR) model is considered to reflect efficiently the long memory. The parameters of the INHAR model are estimated using the conditional least squares estimate and Yule-Walker estimate. Through simulations, bias and standard error are calculated to compare the performance of the estimates. Effects of model fitting to the Korea's IPO are evaluated using performance measures such as mean square error (MAE), root mean square error (RMSE), mean absolute percentage error (MAPE) etc. The results show that INHAR model provides better performance than traditional INAR model. The empirical analysis of the Korea's IPO indicates that our proposed model is efficient in forecasting monthly IPO volumes.

Enhanced Hybrid Privacy Preserving Data Mining Technique

  • Kundeti Naga Prasanthi;M V P Chandra Sekhara Rao;Ch Sudha Sree;P Seshu Babu
    • International Journal of Computer Science & Network Security
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    • v.23 no.6
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    • pp.99-106
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    • 2023
  • Now a days, large volumes of data is accumulating in every field due to increase in capacity of storage devices. These large volumes of data can be applied with data mining for finding useful patterns which can be used for business growth, improving services, improving health conditions etc. Data from different sources can be combined before applying data mining. The data thus gathered can be misused for identity theft, fake credit/debit card transactions, etc. To overcome this, data mining techniques which provide privacy are required. There are several privacy preserving data mining techniques available in literature like randomization, perturbation, anonymization etc. This paper proposes an Enhanced Hybrid Privacy Preserving Data Mining(EHPPDM) technique. The proposed technique provides more privacy of data than existing techniques while providing better classification accuracy. The experimental results show that classification accuracies have increased using EHPPDM technique.

Stock Market Reaction on Olympic Sponsorship Announcement Using Event-study Method

  • Spais, George S.;Filis, George N.
    • Journal of Global Scholars of Marketing Science
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    • v.16 no.2
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    • pp.95-108
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    • 2006
  • The major objective of this study is to test if an Olympic Games sponsorship program can influence investors' behavior: stock returns, stock volatility and transaction volumes. The paper deals with stock market reaction on Olympic sponsorship announcement for service organizations using event study method. Our research intention is to test 440 daily stock prices and transaction volumes, in order investigate the potent influence between the announcement of a grand sport sponsorship program and investors' behavior. For this study we examined the announcement data of three grand sponsors of Olympic Games of Athens 2004 (Alpha Bank. Delta and G.T.O) The main contribution of this study is to examine how stock investors' behavior is influenced by the sponsorship program of companies and to extend research scope of marketing field toward stock market. They authors suggest that organizations interested in influencing investors' behavior should invest in sponsorship activities at the sports' sector.

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Growth Responses of Dieffenbachia amoena 'Marianne' and Begonia rex to Different Lengths and Numbers of Slitwalls in Drainless Containers for Green Technology (녹색기술 무배수구 용기깊이와 슬릿(Slit)차이에 따른 디펜바키아 마리안느와 렉스 베고니아의 생육반응)

  • Ju, Jin-Hee;Yoon, Yong-Han
    • Journal of Environmental Science International
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    • v.21 no.8
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    • pp.931-938
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    • 2012
  • The effects were investigated of different lengths and numbers of slitwalls in drainless containers on growth and change in soil moisture volumes on the growth of Diffenbachia amoena 'Marianne' and Begonia rex. Drainless containers filled with amended soil, with square shape ($240mm{\times}240mm$) were used, as well as three different sets of slitwalls (2, 4 or 8, respectively) in addition to non-slitwall containers. Two indoor foliage plants were grown in slitwall containers in randomized blocks with 3 replications in greenhouse conditions, from March to September, 2009. Soil moisture volumes per container were measured by weighing containers every 2 hours during the day. The change in soil moisture volumes showed considerable differences among slitwalls tested in comparison to control containers before and after twice-weekly irrigation. Particularly, the differences in the S2 (195mm, slitwall 2) containers were significantly greater than other containers tested. For Diffenbachia amoena 'Marianne', plant height, length of leaf, dry weight and fresh weight were higher with S2 containers than with those grown in other containers tested. The Begonia rex with the best quality in terms of plant height, length of leaf and width of leaf was grown in S8 (360mm, slitwall 8) containers. Particularly, statistical analysis has indicated that shoot fresh weights of Begonia rex grown in S8 were 3-fold higher than those grown in CS8 containers. The different results obtained within the two species led us to hypothesize a species-specific influence on indoor foliage plant performance. However, plants of both species grown in slitwall containers showed good results compared with plants grown in non-slitwall containers.

Dosimetric Evaluation of 3-D Conformal and Intensity-modulated Radiotherapy for Breast Cancer after Conservative Surgery

  • Mansouri, Safae;Naim, Asmaa;Glaria, Luis;Marsiglia, Hugo
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.11
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    • pp.4727-4732
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    • 2014
  • Background: Breast cancers are becoming more frequently diagnosed at early stages with improved long term outcomes. Late normal tissue complications induced by radiotherapy must be avoided with new breast radiotherapy techniques being developed. The aim of the study was to compare dosimetric parameters of planning target volume (PTV) and organs at risk between conformal (CRT) and intensity-modulated radiation therapy (IMRT) after breast-conserving surgery. Materials and Methods: A total of 20 patients with early stage left breast cancer received adjuvant radiotherapy after conservative surgery, 10 by 3D-CRT and 10 by IMRT, with a dose of 50 Gy in 25 sessions. Plans were compared according to dose-volume histogram analyses in terms of PTV homogeneity and conformity indices as well as organs at risk dose and volume parameters. Results: The HI and CI of PTV showed no difference between 3D-CRT and IMRT, V95 gave 9.8% coverage for 3D-CRT versus 99% for IMRT, V107 volumes were recorded 11% and 1.3%, respectively. Tangential beam IMRT increased volume of ipsilateral lung V5 average of 90%, ipsilateral V20 lung volume was 13%, 19% with IMRT and 3D-CRT respectively. Patients treated with IMRT, heart volume encompassed by 60% isodose (30 Gy) reduced by average 42% (4% versus 7% with 3D-CRT), mean heart dose by average 35% (495cGy versus 1400 cGy with 3D-CRT). In IMRT minimal heart dose average is 356 cGy versus 90cGy in 3D-CRT. Conclusions: IMRT reduces irradiated volumes of heart and ipsilateral lung in high-dose areas but increases irradiated volumes in low-dose areas in breast cancer patients treated on the left side.

A study on the apparent and partial molal volumes of n-Alkyl amine hydrochloride in water (n-Alkyl amine 鹽酸鹽의 水溶液 中에서의 apparent 및 partial molal volumes에 관한 硏究)

  • Yoon Sang Ki
    • Journal of the Korean Chemical Society
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    • v.13 no.2
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    • pp.121-129
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    • 1969
  • The apparent and partial molal volumes({\phi}\nu$and $V^{\circ}$) of a series of homologous n-alkylamine hydrochlorides $C_nH_{2n+1}NH_3^+Cl^-$, where n varies from zero to four, have been determined by means of a float method at 30$^{\circ}C$ to the fifth decimal place down to 0.01M in aqueous solutions. The experimental results indicate that the partial molal volumes of the salts are almost additive for successive homologues depending on the increment of molecular weight ($CH_2$). It has been observed that the concentration dependence of the ${\Phi}v$ are linear in general and limiting slopes are positive and relatively close to the theoretical values. Anionic partial molal volume of chlorides anion $V^{\circ}_{Cl^-}$ is found to be 18.6 ml $mole^{-1}$, which is in good agreement with the results of other workers. {\phi}\nu$ data also show that in solution the hydrophobic effect of ions are in competition with the charge effect, but the latter, that is, electrostriction seemed to be considerably predominant.

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A Analysis of Freight Volume and Freight Truck Flows for Efficient Urban Goods Movement at Incheon City (인천시의 효율적인 도시물류정비를 위한 화물물동량 및 화물차의 유동특성분석)

  • Yun, Jeong Mi;Park, Sang Chul
    • Journal of the Korean Association of Geographic Information Studies
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    • v.8 no.2
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    • pp.166-174
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    • 2005
  • Plan of Logistics facility and Management of Freight trucks need for Efficient Improvement of Urban Goods Movement. For this, it need to clear flow pattern of Freight volumes and Freight trucks on urban space. Therefor, The purpose of this study is to clear space flow pattern of Freight volumes and Freight trucks as base data for Plan of Urban Goods Movement on Incheon city. Incheon city is selected because it is at sea & air ports and carries out various Activity of Urban Goods Movement. As the result of this study, it understands and analyzes Characteristic on flow pattern of Freight volumes and Freight trucks. Through this study, we'll expect that this results could be contributed in the understand of actual conditions of Freight volume and freight trucks and the basic data for Improvement of urban goods movement and the management policy of freight trucks in urban goods movement.

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Magnetic Resonance Enhancement Pattern as a Predictor of Cement Volume in Vertebroplasty Procedures for Osteoporotic Fractures

  • Lee, Kye Ho;Yoo, Dong Soo;Kim, Yoon Ha
    • Investigative Magnetic Resonance Imaging
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    • v.21 no.3
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    • pp.148-153
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    • 2017
  • Purpose: To identify the differences between injected cement volumes during vertebroplasty procedures according to the enhancement pattern of pre-procedure magnetic resonance imaging (MRI) findings. Materials and Methods: Thirty-two patients who underwent 52 vertebroplasty procedures as well as pre-procedure contrast-enhanced spine MRI in the authors' institution were reviewed retrospectively. The 52 procedures were divided into two groups according to different enhancement patterns shown by pre-procedure MR imaging [E(+) and E(-)]. The volumes of the enhancing/non-enhancing portions of the fractured vertebral body shown by pre-procedural MR imaging were calculated and compared to the volumes of the injected cement during the vertebroplasty procedures. Results: The 52 injections included 28 (56%) in Group E(+) and 24 (44%) in Group E(-). The actual volume ratio of the injected cement to the volume of the non-enhanced or enhanced region calculated based on the contrast-enhanced MRI was $0.22{\pm}0.11(cc/cm^3)$ in the E(+) group and $0.93{\pm}0.62(cc/cm^3)$ in the E(-) group. The average amount of injected cement was significantly different between Group E(+) and Group E(-) (P < 0.001). In addition, the ratio of the injected cement amount to the volume of the enhanced or non-enhanced portion based on the contrast-enhanced MRI in Group E(-) was significantly higher than that of Group E(+) (P < 0.001). Conclusion: Different enhancement patterns shown by pre-procedure MRI can predictors of the injected cement volume during vertebroplasty procedures for osteoporotic fractures.

A Study on the Analysis of Structure and Utility of Topic Index, Syntopicon in Great Books ('위대한 저서'의 토픽색인, 신토피콘의 구조와 효용성 분석에 관한 연구)

  • Lee, Byeong-Ki
    • Journal of the Korean Society for Library and Information Science
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    • v.46 no.2
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    • pp.5-28
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    • 2012
  • Great Books of the Western World(GBWW) is a series of books published in 1952 by Encyclopaedia Britannica to present the famous works in 54 volumes. The series is now in its second edition and contains 60 volumes. A syntopicon compiled by M. Adler is a two-volume index, published as volumes 2 and 3 of GBWW. The syntopicon was coined specifically for this undertaking, which means a collection of topics. Syntopicon lists, under each idea, is where every occurrence of the concept can be located in the collection's famous works. This study aims to analyze the structure and utility of topic index, syntopicon in GBWW. The syntopicon consists of 102 chapters on the 102 ideas. Each chapter is broken down into five distinct sections: the introduction, an outline of topics, references, cross-references, and additional readings. The syntopicon can serve as a reference book, as a selection tool of book to be read, instrument of liberal education, instrument of discovery and research, syntopical reading of other reading material, development tool of convergent education, and analysis tool of works.