• Title/Summary/Keyword: Data Heterogeneity

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A Cryptographic Model to Protect Private Information against Malicious Proxy in Jini (악의적 지니 프록시로부터 비밀 정보 보호를 위한 암호학적 모델)

  • Yang Jong-Phil;Rhee Kyung-Hyune
    • The KIPS Transactions:PartC
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    • v.13C no.1 s.104
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    • pp.27-34
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    • 2006
  • In the near future, people will wish to access many kinds of heterogeneous networks to use their services anytime and anywhere. Owing to the heterogeneity of networks, there must be many kinds of protocols to guarantee secure services. The mobile device can depend in a middleware for accessing services in the heterogeneous networks and the middleware helps the mobile device to communicate with services without blowing concrete protocols. If a secure channel is necessary, the middleware may access a private key in the mobile device to perform a security protocol. In this paper, we focus on the security of a private key in the mobile device against malicious middlewares. To do so, we introduce two models for a user to protect his/her private key against malicious middlewares by generating authentication data(e.g., digital signatures) without keeping the private key in the mobile device.

The Anti-hepatotoxic Effect of Ginseng in Rats: Meta-analysis

  • Kook, Se-Jeong;Han, Hye-Kyoung;Kim, Gun-Hee;Choi, Ki-Heon
    • Journal of Ginseng Research
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    • v.32 no.2
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    • pp.161-170
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    • 2008
  • The aim of this meta-analysis was to systematically investigate the anti-hepatotoxic effect of ginseng in rats induced toxicity which damage to liver. Primary researches were gained on the ScienceDirect database, the DBpia, and the KISS, and the data about the effect factors in plasma and in enzyme were listed as many as possible. The effect factors were alanine transaminase (ALT), aspartate transaminase (AST), liver aminopyrine N-demethylase (AD), liver aniline hydroxylase (AH), liver 3,4-Methylenedioxyamphetamine (liver MDA), cytochrome P450 (P450), serum alkaline phosphatase (ALP), serum lactate dehydrogenase (LDH), cytochrome b5 (Cyto b5), glutathione reductase (GR), Liver glutathione S-transferase (GST), liver glutamyltransferase (GT), Liver (${\gamma}-GCS$), serum liver 3,4-Methylenedioxyamphetamine (serum MDA), serum sorbitol dehydrogenase (SDH), serum total protein (TP), serum ${\gamma}-glutamyltransferase$ (${\gamma}-GT$). To investigate the effect of ginseng, the mean difference (MD) between the group of rats induced by toxicity (RH) and the group of rats induced by toxicity with ginseng (RHG) were combined, and the significance of MDs were tested. The combined MDs were checked the biases caused by heterogeneity among studies and the publication biases, and adjusted by using random effect model and trim and fill method, respectively. The effect about ALT, AST, ALP, LDH, SDH, TP and ${\gamma}-GT$ in plasma factors were significant, and about AD, liver MDA, P450, Cyto b5, GR, GST, GT and ${\gamma}-GCS$ in enzyme factors were significant. The treatment with ginseng supplementation was significantly effected on plasma and enzyme factors of damaged-rats.

Association between dental X-ray exposure and the thyroid cancer risk: A meta-analysis of case-control studies

  • Hwang, Su-Yeon;Kim, Hae-Young;Song, Sun-Mi;Choi, Eun-Sil
    • Journal of Korean society of Dental Hygiene
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    • v.20 no.3
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    • pp.269-279
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    • 2020
  • Objectives: Previous studies have reported inconsistent findings in the association between dental diagnostic X-ray exposure and thyroid cancer. This study was a meta-analysis of case-control studies evaluating the association between exposure to dental radiation and the thyroid cancer risk. Methods: We searched the PubMed and EMBASE databases to identify studies on dental radiation and thyroid cancer risks that were published up to September 2018. Quality of studies was assessed using the Newcastle-Ottawa scale. A fixed-effects model was used to estimate pooled odds ratios (ORs) and 95% confidence intervals (CIs) using STATA 14.0. Potential publication biases were evaluated using Egger's test and Begg's funnel plot. Results: From the literature search, we included six case-control studies in this meta-analysis. The meta-analysis using the fixed-effects model found that dental X-ray exposure was associated with 2.34 times increased risk for thyroid cancer (OR=2.34, 95% CI=1.79-3.21). There was no heterogeneity in the data (p=0.662, I2 =0%). Egger's test showed that there was no publication bias (p=0.532). Conclusions: This meta-analysis confirmed the association of dental X-ray exposure and thyroid cancer risk. The current results underscore the importance of applying safety regulations at dental clinics to protect thyroid glands during dental radiography examinations.

A Generic Interface for Internet of Things (IoT) Platforms (IoT 플랫폼을 위한 범용 인터페이스)

  • Kim, Mi;Lee, Nam-Yong;Par, Jin-Ho
    • KIPS Transactions on Software and Data Engineering
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    • v.7 no.1
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    • pp.19-24
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    • 2018
  • This paper presents an IoT platform of common interfaces that are flexible IoT applications and Connect the smart devices. The IoT platform includes automatic collaboration discovery the smart Device. It is different things case with connection each device through IoT Platforms are each device and application service. Due to these heterogeneities, it is quite advantages to develop applications working with derived IoT services. This circumstance needs the generic interface and results in a range of IoT architectures by not only the environments settings and discovery resource but also varied uniqe to implementation services working with IoT applications. Therefore, this suggestion of solve the problems and make it possible independent platforms always alive to connection with each devices based on the generic interface. The generic interface is heterogeneity-driven solve the problems and effectively contributions a platform that could be operated in diverse IoT Platforms.

An Experimental Study of the Effect of the Test-well Arrangement on the Partitioning Interwell Tracer Test for the Estimation of the NAPL Saturation (지하수 유동 방향에 대한 관정배열이 분배추적자 시험에 미치는 영향 분석)

  • Kim, Bo-A;Kim, Yongcheol;Yeo, In Wook;Ko, Kyung-Seok
    • Journal of Soil and Groundwater Environment
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    • v.19 no.3
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    • pp.111-122
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    • 2014
  • Partitioning interwell tracer test (PITT) is a method to quantify and qualify a site contaminated with NAPLs (Non-Aqueous Phase Liquids). Analytical description of PITT assumes that the injection-pumping well pair is on the line of the ambient groundwater flow direction, but the test-well pair could frequently be off the line in a real field site, which could be an erroneous factor in analyzing PITT data. The purpose of this work is to study the influence of the angle of the test-well pair on the ambient groundwater flow direction based on the result from PITT. From the experiments, it was found that the obliqueness of the test-well pair to the ambient groundwater flow direction could affect the tracer test resulting in a decreased NAPL estimation efficiency. In case of an oblique arrangement of the test-well pair to the ambient flow direction, it was found that the injection of a chase fluid could enhance the estimation efficiency. An increase of the pumping rate could enhance the recovery rate but it cannot be said that a high pumping rate can increase the test efficiency because a high pumping rate cannot give partitioning tracers enough time to partition into NAPLs. The results have a implication that because the arrangement of the test-well pair is a controlling factor in performing and interpreting PITT in the field in addition to the known factors such as heterogeneity and the source zone architecture, flow direction should be seriously considered in arranging test-well pair.

Deprivation and Mortality at the Town Level in Busan, Korea: An Ecological Study

  • Choi, Min-Hyeok;Cheong, Kyu-Seok;Cho, Byung-Mann;Hwang, In-Kyung;Kim, Chang-Hun;Kim, Myoung-Hee;Hwang, Seung-Sik;Lim, Jeong-Hun;Yoon, Tae-Ho
    • Journal of Preventive Medicine and Public Health
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    • v.44 no.6
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    • pp.242-248
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    • 2011
  • Objectives: Busan is reported to have the highest mortality rate among 16 provinces in Korea, as well as considerable health inequality across its districts. This study sought to examine overall and cause-specific mortality and deprivation at the town level in Busan, thereby identifying towns and causes of deaths to be targeted for improving overall health and alleviating health inequality. Methods: Standardized mortality ratios (SMRs) for all-cause and four specific leading causes of death were calculated at the town level in Busan for the years 2005 through 2008. To construct a deprivation index, principal components and factor analysis were adopted, using 10% sample data from the 2005 census. Geographic information system (GIS) mapping techniques were applied to compare spatial distributions between the deprivation index and SMRs. We fitted the Gaussian conditional autoregressive model (CAR) to estimate the relative risks of mortality by deprivation level, controlling for both the heterogeneity effect and spatial autocorrelation. Results: The SMRs of towns in Busan averaged 100.3, ranging from 70.7 to 139.8. In old inner cities and towns reclaimed for replaced households, the deprivation index and SMRs were relatively high. CAR modeling showed that gaps in SMRs for heart disease, cerebrovascular disease, and physical injury were particularly high. Conclusions: Our findings indicate that more deprived towns are likely to have higher mortality, in particular from cardiovascular disease and physical injury. To improve overall health status and address health inequality, such deprived towns should be targeted.

A Study on Acculturation of North Korean Defectors in South Korea (북한이탈주민의 한국 내 문화적응)

  • Han, Jin-Sook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.11
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    • pp.5027-5033
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    • 2011
  • The purpose of this study was to analyze a qualitative research on the essential structure of the acculturation of North Korean defectors, who settled in South Korea. The participants in this study were nine North Korean defectors who had resided in the city of D, South Korea, for three years or more after defecting from North Korea. After an in-depth interview, collected data were analyzed by applying Colaizzi's phenomenological method. As a result, their acculturation were classified into three categories : 'heterogeneity coming from different cultures', 'undergoing various sufferings after defection', and 'trying to tide over the difficulties in the actuality'. And 11 clusters of theme were selected. It's basically meant in this study to find out problems North Korean Defectors encountered and their process of overcoming the difficulties in an effort to step up the acculturation of the new settlers and ease their difficulties. And it's suggested that adjustment programs should be provided for them to fit into South Korean society.

A Model for Effective Customer Classification Using LTV and Churn Probability : Application of Holistic Profit Method (고객의 이탈 가능성과 LTV를 이용한 고객등급화 모형개발에 관한 연구)

  • Lee, HoonYoung;Yang, JooHwan;Ryu, Chi Hun
    • Journal of Intelligence and Information Systems
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    • v.12 no.4
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    • pp.109-126
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    • 2006
  • An effective customer classification has been essential for the successful customer relationship management. The typical customer rating is carried out by the proportionally allocating the customers into classes in terms of their life time values. However, since this method does not accurately reflect the homogeneity within a class along with the heterogeneity between classes, there would be many problems incurred due to the misclassification. This paper suggests a new method of rating customer using Holistic profit technique, and validates the new method using the customer data provided by an insurance company. Holistic profit is one of the methods used for deciding the cutoff score in screening the loan application. By rating customers using the proposed techniques, insurance companies could effectively perform customer relationship management and diverse marketing activities.

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An Application of Ordinations to Kwangnung Forest (광릉 삼림 군집에 대한 Ordination 방법의 적용)

  • 강윤순
    • Journal of Plant Biology
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    • v.25 no.2
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    • pp.83-99
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    • 1982
  • In this study, thirty-two stands in Kwangnung forest located in the central part of Korea were preferentially selected. In each stand, all stems for trees and shrubs were recorded by species and their girths were measured down to 5cm. In addition, several enviromental factors such as field soil pH, field soil moisture, soil compressibility, depth of soil, thickness of litter layer, elevation and basal area were measured. Three soil cores were sampled and various physical and chemcial properties was determined. The vegetational data were subjected to three kinds of multivariate ordination(PO, PCA, RA). The results suggested that Kwangnung forest was consisted of three forest types: coniferous, mixed and broad leaved forest communities. The relation between the stand scores of ordination and several environmental factors were investigated in terms of correlation analysis in order to examine the relationships between the vegetation and certain environmental factors. As a result of this analysis, the amount of sand content in A1 horizon decreased frm the coniferous to broad leaved forest, while maximum field capacity, pore space, exchangeable cations, loss on ignition, soil pH nad the amount of total nitrogen had a tendancy to increase significantly. However, easily soluble phosphorus appeared to have little to do with the forest types. The result of species ordination of centered-standardized PCA suggested that the major successional pathway in Kwangnung forest was; Pinus densifloralongrightarrowQuercus mongolica, Q. serrata, Q. alienalongrightarrowCarpinus laxifloralongrightarrowC. erosa in sequence. This trend is in good agreement with the past studies. In three kinds of ordination (centered PCA, centered-standardized PCA and RA) based on nineteen species and twenty-five stands, the total variances accounted for the first three axes were 77%, 46% and 63% respectively. The estimated beta diversity in Kwangnung forest assumed as a coenocline, was 1.5~1.8 HC. Increasing the effect of the sampling errors on ordination perfermance, this low heterogeneity seems to cause the poor concentration of the total variance. The results from the four kinds of ordination were in good agreement with each other, especially between PO, centered-standardized PCA and RA appeared robust. It seems to be worthy of applying multivariate method for analyzing other forest communities in Korea.

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The Effects of Balloon-Guide Catheters on Outcomes after Mechanical Thrombectomy in Acute Ischemic Strokes : A Meta-Analysis

  • Ahn, Jun Hyong;Cho, Steve S.;Kim, Sung-Eun;Kim, Heung Cheol;Jeon, Jin Pyeong
    • Journal of Korean Neurosurgical Society
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    • v.62 no.4
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    • pp.389-397
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    • 2019
  • Objective : Mechanical thrombectomies with balloon-guide catheters (BGC) are thought to improve successful recanalization rates and to decrease the incidence of distal emboli compared to thrombectomies without BGC. We aimed to assess the effects of BGC on the outcomes of mechanical thrombectomy in acute ischemic strokes. Methods : Studies from PubMed, EMBASE, and the Cochrane library database from January 2010 to February 2018 were reviewed. Random effect model for meta-analysis was used. Analyses such as meta-regression and the "trim-and-fill" method were additionally carried out. Results : A total of seven articles involving 2223 patients were analyzed. Mechanical thrombectomy with BGC was associated with higher rates of successful recanalization (odds ratio [OR], 1.632; 95% confidence interval [CI], 1.293-2.059). BGC did not significantly decrease distal emboli, both before (OR, 0.404; 95% CI, 0.108-1.505) and after correcting for bias (adjusted OR, 1.165; 95% CI, 0.310-4.382). Good outcomes were observed more frequently in the BGC group (OR, 1.886; 95% CI, 1.564-2.273). Symptomatic intracranial hemorrhage and mortality did not differ significantly with BGC use. Conclusion : Our meta-analysis demonstrates that BGC enhance recanalization rates. However, BGC use did not decrease distal emboli after mechanical thrombectomies. This should be interpreted with caution due to possible publication bias and heterogeneity. Additional meta-analyses based on individual patient data are needed to clarify the role of BGC in mechanical thrombectomies.