• Genomics & Informatics
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• v.20 no.3
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• pp.34.1-34.11
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• 2022

Multilevel analysis is an appropriate and powerful tool for analyzing hierarchical structure data widely applied from public health to genomic data. In practice, however, we may lose the information on multiple nesting levels in the multilevel analysis since data may fail to capture all levels of hierarchy, or the top or intermediate levels of hierarchy are ignored in the analysis. In this study, we consider a multilevel linear mixed effect model (LMM) with single imputation that can involve all data hierarchy levels in the presence of missing top or intermediate-level clusters. We evaluate and compare the performance of a multilevel LMM with single imputation with other models ignoring the data hierarchy or missing intermediate-level clusters. To this end, we applied a multilevel LMM with single imputation and other models to hierarchically structured cohort data with some intermediate levels missing and to simulated data with various cluster sizes and missing rates of intermediate-level clusters. A thorough simulation study demonstrated that an LMM with single imputation estimates fixed coefficients and variance components of a multilevel model more accurately than other models ignoring data hierarchy or missing clusters in terms of mean squared error and coverage probability. In particular, when models ignoring data hierarchy or missing clusters were applied, the variance components of random effects were overestimated. We observed similar results from the analysis of hierarchically structured cohort data.

• Korean Journal of Radiology
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• v.22 no.4
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• pp.663-671
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• 2021

Objective: To determine the association of macrocalcification and rim calcification with malignancy and to stratify the malignancy risk of thyroid nodules with macrocalcification and rim calcification based on ultrasound (US) patterns. Materials and Methods: The study included a total of 3603 consecutive nodules (≥ 1 cm) with final diagnoses. The associations of macrocalcification and rim calcification with malignancy and malignancy risk of the nodules were assessed overall and in subgroups based on the US patterns of the nodules. The malignancy risk of the thyroid nodules was categorized as high (> 50%), intermediate (upper-intermediate: > 30%, ≤ 50%; lower-intermediate: > 10%, ≤ 30%), and low (≤ 10%). Results: Macrocalcification was independently associated with malignancy in all nodules and solid hypoechoic (SH) nodules (p < 0.001). Rim calcification was not associated with malignancy in all nodules (p = 0.802); however, it was independently associated with malignancy in partially cystic or isoechoic and hyperechoic (PCIH) nodules (p = 0.010). The malignancy risks of nodules with macrocalcification were classified as upper-intermediate and high in SH nodules, and as low and lower-intermediate in PCIH nodules based on suspicious US features. The malignancy risks of nodules with rim calcification were stratified as low and lower-intermediate based on suspicious US features. Conclusion: Macrocalcification increased the malignancy risk in all and SH nodules with or without suspicious US features, with low to high malignancy risks depending on the US patterns. Rim calcification increased the malignancy risk in PCIH nodules, with low and lower-intermediate malignancy risks based on suspicious US features. However, the role of rim calcification in risk stratification of thyroid nodules remains uncertain.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1996.04a
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• pp.342-348
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• 1996

This paper describes the formulation for the vibration analysis of cylindrical shells with stiffeners by the transfer influence coefficient method. This method was developed on the base of the concept of the successive transmission of dynamic influence coefficients. The simple computational results from a personal computer demonstrate the validity of the present method, that is, the numerical high accuracy and the flexibility of programming, are compared with results of the transfer matrix method. It is also confirmed that the present algorithm could provide the solutions of high accuracy for system with a number of intermediate rigid supports. And all boundary conditions and the intermediate stiff supports such as intermediate rigid supports between shell and foundation can be treated only by adequately controlling the values of the spring constants.

• Journal of the Korean Society of Tobacco Science
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• v.5 no.2
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• pp.25-32
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• 1983

To obtain basic information on the breeding of burley tobacco, classification of 41 varieties was carried out by using the cluster analysis of correlation coefficients and taxonomic distance based on twenty-one agromonic characters. Eight characters, such as days to flowering, length of flower axis, internode length, leaf length, yield, leaf angle to stem, vein angle to midrib and plant height, were useful in monothetic classification. Forty-one varieties were classified into four groups (I, II, III and IV) with weighted variable group method (WVGM ) and weighted jai. group method(WPGM), whereas the results classification of 33 varieties among them by WVGM were coincident with the results by WPGM. As for the characteristics of each group, group I related to late maturity, tall height and high yield, group II related to intermediate maturity, tall height and low yield, group 19 related to early maturity, intermediate height and low yield, and group W related to early maturity, short height and intermediate yield.

• Structural Engineering and Mechanics
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• v.55 no.1
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• pp.137-160
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• 2015

The one-way (two-way) flexural strength of RCC prisms (circular slabs) reinforced with glass fiber textiles is addressed. To this end, alkaline-resistant glass fiber textiles with three surface weights were used in the composite, the matrix concrete was designed with zero/nonzero slump, and the textiles were used with/without an intermediate layer provided by epoxy resin and sand mortar. Prisms were tested under a four-point loading apparatus and circular slabs were placed on simple supports under a central load. Effects of the amount and geometry of reinforcement, matrix workability, and the intermediate layer on the ultimate load and deflection were investigated. Results revealed that, with a specific reinforcement amount, there is an optimum textile tex for each case, depending on the matrix mix design and the presence of intermediate layer. Similar results were obtained in one-way and two-way bending tests.

• Journal of applied mathematics & informatics
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• v.32 no.5_6
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• pp.621-633
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• 2014

In this paper, we introduce a general iterative algorithm for asymptotically quasi-${\phi}$-nonexpansive mappings in the intermediate sense to have the strong convergence in the framework of Banach spaces. The results presented in the paper improve and extend the corresponding results announced by many authors.

• Restorative Dentistry and Endodontics
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• v.32 no.5
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• pp.445-458
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• 2007

The purpose of this study was to evaluate the bond strength of a new Single step system with different curing mode composites, and to evaluate the effect of the intermediate resins which have different hydrophilicity on bonding ability by means of the micro shear bond testing and TEM examination for the adhesive interface. The adhesive used in this study was an experimental single step system (Bisco Inc., Schaumburg IL). Experimental groups were produced by using six kinds of intermediate resin having different hydrophilicity that was hydrophilic, hydrophobic and most hydrophobic resin and as filled or not after applying adhesive. Each experimental group was further divided into two subgroups whether the adhesive was light cured or not. Dual cured composite (Bis Core, Bisco Ltd., Schaumburg, IL) was placed on the adhesive layer as light cure or self cure mode. The results or bond strength were statistically analyzed using one way ANOVA and multiple comparisons are made using Tukey's test at ${\alpha}\;<\;0.05$ level. The results of this study were as follows ; 1. The application of intermediate resin did not increase the bond strength for light cured composite. 2. The bond strength of an experimental adhesive with self cured composite was significantly increased by the application of intermediate resin layer. 3. The bond strength of adhesive was irrespective of the cure or not of itself before intermediate resin layer applied. 4. As applied hydrophilic resin layer was, the initial bond strength was higher than both hydrophobic and most hydrophobic one used but there was no significance. Using a single step adhesive with dual/self cured composite, the incompatibility between both of them should be solved by the application of intermediate hydrophobic resin to reduce the adhesive permeability. However, Single step adhesive can be used in the light cured composite restoration without any decrease of the initial bond strength.

• Journal of Technology Innovation
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• v.18 no.2
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• pp.91-120
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• 2010

This paper examines the effect of bargaining power over intermediate goods prices on innovation and economic growth using a Schumpeterian growth model. The notion of "intermediate goods prices" broadly indicates the reward to innovators including innovative SMEs as well as intermediate goods producers that are vertically integrated to big businesses. From this viewpoint, this paper sets up a Schumpeterian growth model that incorporates the market power between final goods producers and intermediate goods producers. The results show that the reduction of intermediate goods prices slows down long-run growth rates as it erodes the reward to innovations. Lower intermediate goods prices decrease marginal productivity of capital and real interest rates. However, the harmful effect of lower profits on innovations outweighs the beneficial effect of lower interest rates. Simulations using Korea's data for various cases show that in all cases the policies that raise the share of intermediate goods producers are as powerful as the R&D subsidy policies in raising growth rates. Therefore, fair trade policies that enable intermediate goods producers-especially SMEs to obtain more fruits of innovations will be helpful for long-run economic growth.

• Journal of the Korean Institute of Rural Architecture
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• v.26 no.2
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• pp.65-72
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• 2024

In order to analyze the impact of fine dust generated from a construction waste intermediate processing site on the surrounding areas, diverse types of samples were collected from inside the site and surrounding areas. The impact analysis results of samples are as follows. (1) Compared to the air quality management standards by the Ministry of Environment, the concentration of fine dust within the site was 30 to 46% for PM10 and 14 to 42% for PM2.5, which was not much different from the general air quality level. (2) It was found that PM10 within the site may have a partial effect on the air quality, but when the blocking facilities in the site, wheel washing facilities at vehicle entry and exit route, and sprinkler during working were maintained, the impact on the nearby area was not high. (3) In the case of PM2.5, its concentration was influenced more by the exhaust fumes from work vehicles than fine dust generated during construction waste processing. Since the PM2.5 concentrations in the site and surrounding area were not much different from the general air quality, there was little correlation with the work impact of construction waste intermediate processing sites. (4) Pb, an indicator of heavy metal components, was within 50ng/m³ in all three sites, which was 10% of the domestic management standard and equivalent to the general air quality level. The complaints from residents in nearby areas were filed using indicators based on visual and experiential information in their daily lives, so even if the survey results of environmental impact by the construction intermediate waste processing site are lower than the standard, nearby residents can feel it better than such numerical information. Therefore, specific activities to reduce find dusts should be continuously continued.

• The Korean Journal of Malacology
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• v.27 no.3
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• pp.199-204
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• 2011

We studied possibility of the sowing culture at the bottom after intermediate culture as a method for raising the survival of the Purplish Washington clam, Saxidomus purpuratus. The pearl net ($35cm(W){\times}35cm(B){\times}20cm(H)$) for S. prupuratus spat during the period of intermediate culture (hanging culture) from April to October in 2010. The pearl net (100 inds./net) was installed at two stations (Namhae and Pohang) being about 3-4 m in water depth. After hanging culture, S. prupuratus spat sowed in the bottom of the Gangjin Bay. The survivals (%) of intermediate culture of this species at Namhae station and Pohang station were 73% and 74%, respectively. Daily growth rate of mean shell length and mean weight in Namhae station were higher than those in Pohang station. After sowing at the bottom of the Gangjin Bay, its survival (%) showed 73.98% in January 2011. These results suggested the possibility of the intermediate culture as hanging culture for raising survival rate of S. prupuratus.