• Water Engineering Research
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• v.3 no.1
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• pp.31-44
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• 2002

The effect of diurnal cycle, intermittent visit of observation satellite, sensor installation, partial coverage of remote sensing, heterogeneity of soil properties and precipitation to the soil moisture estimation error were analyzed to present the global sampling strategy of soil moisture. Three models, the theoretical soil moisture model, WGR model proposed Waymire of at. (1984) to generate rainfall, and Turning Band Method to generate two dimensional soil porosity, active soil depth and loss coefficient field were used to construct sufficient two-dimensional soil moisture data based on different scenarios. The sampling error is dominated by sampling interval and design scheme. The effect of heterogeneity of soil properties and rainfall to sampling error is smaller than that of temporal gap and spatial gap. Selecting a small sampling interval can dramatically reduce the sampling error generated by other factors such as heterogeneity of rainfall, soil properties, topography, and climatic conditions. If the annual mean of coverage portion is about 90%, the effect of partial coverage to sampling error can be disregarded. The water retention capacity of fields is very important in the sampling error. The smaller the water retention capacity of the field (small soil porosity and thin active soil depth), the greater the sampling error. These results indicate that the sampling error is very sensitive to water retention capacity. Block random installation gets more accurate data than random installation of soil moisture gages. The Walnut Gulch soil moisture data show that the diurnal variation of soil moisture causes sampling error between 1 and 4 % in daily estimation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.2
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• pp.422-430
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• 2008

Data integration is techniques to combine heterogeneous data from different sources, and to allow users to transparently access all data from multiple sources via a single view. The difficulty with data integration is data heterogeneity (i.e. schema heterogeneity, semantic heterogeneity). Richer semantics of data is a major factor in resolving conflicts among heterogeneous data sources. As UML class model represents only schema-based semantics of data, alternative methods such as ontology is useful for representing additional semantics. This paper proposes a method for integrating two data sources with UML class models by using an analysis of their ontologies. In our framework, ontology will be applied to describe semantics of data in each source. Then the ontologies are analysed and compared to determine their similarities and differences. The result of the comparison is used to devise an integrated ontology that will enable querying on the integrated information.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.35 no.3
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• pp.48-65
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• 2022

Objectives : This study was conducted to find out the effectiveness and safety of herbal medicine eye drops on conjunctivitis. Methods : We searched randomized controlled trials on conjunctivitis through 10 DBs from the start to April 27, 2022. Study collection and data extraction, and evaluation of risk of bias were conducted by two independent researchers. The evaluation of the risk of bias in included RCTs was carried out by using Cochrane risk-of-bias tool. And the data synthesis was conducted by using Review Manager(RevMan, ver.5.4). Results : Total of 106 studies are researched and 7 studies of them are finally included. 1. The herbal medicine eye drops are more effective on than the western medicine eye drops, but the heterogeneity was very high. So we conducted sensitivity analysis and compared to the herbal medicine eye drops and the western medicine eye drops, the total effective rate was higher in the herbal medicine eye drops and the heterogeneity was somewhat reduced. 2. In the subgroup analysis, Fufang Xiongdan eye drops and Houttuynia cordata Thunb eye drops are more effective than the western medicine. It may represent substantial heterogeneity. 3. In the subgroup analysis, the herbal medicine eye drops are more effective than antibiotic and antiviral eye drops on acute bacterial conjunctivitis, but showed high heterogeneity. On the other hand, the herbal medicine eye drops are more effective than antibiotic and antiviral eyed drops on acute viral conjuctivitis and showed low heterogeneity. 4. In the subgroup analysis, we compared the effectiveness of herbal and western medicine eye drops according to total effectiveness rate evaluation methods. When comparing the studies calculating the total effective rate by the sum of 'Cured', 'Significantly Impaired', and 'Improved', the effective rate of the herbal medicine eye drops was higher than that of the western medicine eye drops, and the heterogeneity was very low. 5. In most studies, side effects of herbal medicine eye drops were absent or mild. Conclusions : This study shows that herbal medicine eye drops may be more effective than western medicine eye drops and have safety. But further researches are needed to resolve the heterogeneity of this study.

• Journal of the Korean Data and Information Science Society
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• v.19 no.2
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• pp.621-634
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• 2008

This paper addresses the problem of testing whether the means in several inverse Gaussian populations with heterogeneity are equal. The analysis of reciprocals for the equality of inverse Gaussian means needs the assumption of equal scale parameters. We propose Bayesian model selection procedures for testing equality of the inverse Gaussian means under the noninformative prior without the assumption of equal scale parameters. The noninformative prior is usually improper which yields a calibration problem that makes the Bayes factor to be defined up to a multiplicative constant. So we propose the objective Bayesian model selection procedures based on the fractional Bayes factor and the intrinsic Bayes factor under the reference prior. Simulation study and real data analysis are provided.

• Journal of the Korean Data and Information Science Society
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• v.19 no.4
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• pp.1429-1440
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• 2008

In a meta-analysis combining the results from different clinical trials, it is important to consider the possible heterogeneity in outcomes between trials. Such variations can be regarded as random effects. Thus, random-effect models such as HGLMs (hierarchical generalized linear models) are very useful. In this paper, we propose a HGLM framework for analyzing the binominal response data which may have variations in the odds-ratios between clinical trials. We also present the prediction intervals for random effects which are in practice useful to investigate the heterogeneity of the trial effects. The proposed method is illustrated with a real-data set on 22 trials about respiratory tract infections. We further demonstrate that an appropriate HGLM can be confirmed via model-selection criteria.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.2
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• pp.40-46
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• 2022

Recently, as the need for data access by integrating information in a distributed cloud environment increases in enterprise-wide enterprises, interoperability for collaboration between existing legacy systems is emphasized. In order to interconnect independent legacy systems, it is necessary to overcome platform heterogeneity and semantic heterogeneity. To solve this problem, middleware was built using EMRA (Extended MetaData Registry Access) based on ISO/IEC 11179. However, the designed middleware cannot guarantee the efficiency of information utilization because it does not have an adjustment function for each node's resource status and work status. Therefore, it is necessary to manage and adjust the legacy system. In this paper, we coordinate the correct data access between the information requesting agent and the information providing agent, and integrate it by designing a cooperative agent responsible for information monitoring and task distribution of each legacy system and resource management of local nodes. to make efficient use of the available information.

• Journal of Technology Innovation
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• v.9 no.2
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• pp.34-55
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• 2001

With increasing globalization, a proper policy for global inter-city networking strongly required, which presumes the study on the heterogeneity among regional innovation systems. While surveying the research results of the Evolutionary Economics, 1 stress that regional systems of innovation differ in technological capacities, industrial structures, institutional arrangements and socio-cultural features. 1 make the empirical investigation based on the data of Busan and Hamburg, making clear the regional specificities among regional innovation systems. The results show that regional systems of innovation in Busan and Hamburg are quitely asymmetric. They suggest also the limitation of neo-classical assumption on the ‘homogeneous production function’ and that policy-makers in regions should make the policy for ‘global inter-cities networking’, based on perspectives of regional heterogeneity.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.10a
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• pp.109-114
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• 1995

A preliminary study of the heterogeneity effect of spent P% fuel in CANDU was made using a reduced spent PWR fuel data base. The instantaneous core simulation has shown that the refueling ripple in the CANDU reactor is large if the spent PWR fuel is directly used. But the fuel heterogeneity effect can be reduced appreciably by blending spent PWR fuel with a small amount of fresh UO$_2$. The refueling simulation has shown that the operating margins of 6.0% and 8.7% are achievable for the peak channel and bundle powers, respectively, with the blended fuel.

• Geotechnical Engineering
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• v.13 no.1
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• pp.85-100
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• 1997

The heterogeneity of hydraulic conductivity of Metropolitan Waste Landfill is analized by using geostatistical methods and the contaminant transport analysis is performed by using heterogeneous hydraulic conductivity. The hydraulic conductivity data are obtained from laboratory pressurized permeability tests and the insitu, Slug test. Geostatistical methods used in this analysis are Ordinary Kriging and conditional simulation. It is concluded that the heterogeneities of hydraulic conductivity obtained from conditional simulation are greater than those from Ordinary Kriging analysis. The movement of the contaminant on the hydraulic conductivity with greater heterogeneity obtained from conditional simulation is faster than that observed in Ordinary Kriging analysis.

• The Korean Journal of Applied Statistics
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• v.11 no.2
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• pp.423-433
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• 1998

In agricultural field experiments, the completely randomized block design is often used for the analysis of variety trials. An important assumption is that every experimental unit in each block has the some fertility. But, in most agricultural field experiments there often exists a systematic heterogeneity in fertility among the experimental units. To account for the heterogeneity, we propose to use the hierarchical generalized linear models. We compare our analysis of the data from Scottish Agricultural colleges list with that using Markov chain Monte Carlo method.