• Communications for Statistical Applications and Methods
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• v.14 no.1
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• pp.169-182
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• 2007

Receive operating characteristic (ROC) approach can be employed to rank candidate genes from a microarray experiment, in particular, for the biomarker development with the purpose of population screening of a cancer. In the cancer microarray experiment based on n patients the researcher often wants to compare the tumor tissue with the normal tissue within the same individual using a common reference RNA. Ideally, this experiment produces n pairs of microarray data. However, it is often the case that there are missing values either in the normal or tumor tissue data. Practically, we have $n_1$ pairs of complete observations, $n_2$ "normal only" and $n_3$ "tumor only" data for the microarray. We refer to this data set as a mixed data set. We develop a ROC approach on the mixed data set to rank candidate genes for the biomarker development for the colorectal cancer screening. It turns out that the correlation between two ranks in terms of ROC and t statistics based on the top 50 genes of ROC rank is less than 0.6. This result indicates that employing a right approach of ranking candidate genes for the biomarker development is important for the allocation of resources.

• Journal of Environmental Impact Assessment
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• v.21 no.2
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• pp.247-254
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• 2012

This paper seeks for the set-up plan in the reasonable target area of environmental assessment. Domestically, the target area of environmental assessment is set up by the adjustment of opinion collection about the assessment scope result of an environmental factor. In a foreign country, the boundary of the target area for a development project is established with the environmental, economical, and social viewpoint based on the standard for significantly environmental impact. Based on the analysis of the present condition at home and abroad, the first set-up plan for the reasonable target area of environmental assessment is the preparation of the detailed term definition related to the target area of environmental assessment. The second is the arrangement of the judgement standard for significantly environmental impact. The quantitative assesment item can apply the present standard or regulation, and the qualitative assessment item can establish the standard based on factual and objective data. The last is the preparation of the reference material or the guideline for deciding the initial target area by the judgement standard and determining the final target area by opinion collection in the stage of scoping.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.2
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• pp.149-155
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• 2012

This paper provides an efficient model predictive control for the output voltage control of three-phase inverter system which includes output LC filters. Use of SVPWM (Space Vector Pulse-Width-Modulation) and the rotating d-q frame is made to obtain an input constrained dynamic model of the inverter system. From the measured/estimated output current and reference output voltage, corresponding equilibrium values of the inductor current and the control input are computed. Derivation of a feasible and invariant set around the equilibrium state is made and then a receding horizon strategy which steers the current state deep into the invariant set is proposed. In order to remove offset error, use of disturbance observer is made in the form of state estimator. The efficacy of the proposed method is verified through simulations.

• Journal of Auto-vehicle Safety Association
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• v.13 no.4
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• pp.33-38
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• 2021

This paper presents a comparative study between the parameter-optimized Pacejka model and artificial neural network model for the tire force estimation. The two different approaches are investigated and compared in this study. First, offline optimization is conducted based on Pacejka Magic Formula model to determine the proper parameter set for the minimization of tire force error between the model and test data set. Second, deep neural network model is used to fit the model to the tire test data set. The actual tire forces are measured using MTS Flat-Track test platform and the measurements are used as the reference tire data set. The focus of this study is on the applicability of machine learning technique to tire force estimation. It is shown via the regression results that the deep neural network model is more effective in describing the tire force than the parameter-optimized Pacejka model.

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.293-301
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• 2016

High-quality gene sets are necessary for functional research of genes. Although Perilla is a commonly cultivated oil crop and vegetable crop in Southeast Asia, the quality of its available gene set is insufficient. To construct a high-quality Perilla gene set, we sequenced mRNAs extracted from different tissues of Perilla citriodora, the wild species (2n = 20) of Perilla. To make a high-quality gene set for P. citriodora, we compared the quality of assemblies produced by Velvet and Trinity, the two well-known de novo assemblers, and improved the de novo assembly pipeline by optimizing k-mers and removing redundant sequences. We then selected representative transcripts for loci according to several criteria. The improved assembly yielded a total of 86,396 transcripts and 38,413 representative transcripts. We evaluated the assembled transcripts by comparing them to 638 homologous Arabidopsis genes involved in fatty acid and TAG biosynthesis pathways. High proportions of full-length genes and transcripts in the assembled transcripts matched known genes in other species, indicating that the P. citriodora gene set can be applied in future functional studies. Our study provides a reference P. citriodora gene set for further studies. It will serve as valuable genetic resource to elucidate the molecular basis of various metabolisms.

• Journal of the Korea Society of Computer and Information
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• v.17 no.8
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• pp.71-80
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• 2012

Much research has been recently accomplished for standardization in cloud computing. However, little research on standardization of data sharing and exchanging has been studied. Most of all, the corresponding standardization organization suggests no specific standardization items and reference model. This paper defines the current standardization problems and proposes a set of specific standardization items and a reference model for supporting the semantic interoperability. To achieve the goal of this paper, the overall standardization trend in cloud computing is first analyzed. Especially, this paper describes the status of standard development for addressing the semantic interoperability of data. This paper also defines the potential standardization items based on the concepts of standards in the data exchanging and management field, which are used for developing standards in various fields. Finally, the reference model is describe to show the relationships between items and overall semantic interoperability process. This paper can be used as a guideline for development of standards and also can facilitate standardization of cloud computing.

• Journal of Korea Spatial Information System Society
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• v.2 no.1 s.3
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• pp.57-62
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• 2000

Open GIS Consortium(OGC) provides with Simple Features Specification for OLE/COM which is a system object technology of interoperability and reusable capability. In this research, the Spatial Reference System(SRS) component is developed based on the OGC specification using ATL. The component presents 44 map projections and transformations between different geographic coordinate systems utilizing the seven parameter(Bursa Wolf) and Molodenski's methods, a user can set up all objects and its attributes comprising SRS and can create SRS and save its setting using predefined text, WellKnownText. The Spatial Reference System component can be easily implemented into the variety of GIS software so that it reduces the developing time for a system and defines new reference system without difficulty.

• Korean Journal of Clinical Pharmacy
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• v.19 no.1
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• pp.50-60
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• 2009

Highly variable drugs (within-subject variability greater than 30%) have been difficult to meet current regulatory acceptance criteria using a reasonable number of study subjects. In this study, we reviewed previous studies presenting alternative approaches for bioequivalence evaluation of highly variable drugs, and focused on an approach for widening the bioequivalence acceptance limits using within-subject variability. We discussed the suggested five solutions for highly variable drug including the deletion of $C_{max}$ of the bioequivalence criteria, direct expansion of bioequivalence limit, multiple dose studies in steady state, bioequivalence assessment on the metabolite, add-on study, and widening the bioequivalence acceptance limits based on reference variability. The methods for widening of bioequivalence limits based on reference variability are scaled average bioequivalence containing within-subject variability on reference drug (${\sigma}_{WR}$), population bioequivalence derived from total variability on reference drug (${\sigma}_{TR}$) and test drug (${\sigma}_{TT}$), and individual bioequivalence derived from subject by formulation interaction variability (${\sigma}_D$) and within subject variability on reference drug (${\sigma}_{WR}$) and test drug (${\sigma}_{TR}$). To apply these methods, the switching variability (${\sigma}_0$) will have to be set by the regulatory authorities. The proposals of bioequivalence evaluation approach for the highly variable in Korea are presented for both of new drug and reevaluation drug.

• Earthquakes and Structures
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• v.15 no.6
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• pp.595-603
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• 2018

Shake table testing has been regarded as one of the most effective experimental approaches to evaluate seismic response of structural systems subjected to earthquakes. However, reproducing a prescribed acceleration time history precisely over the frequency of interest is challenging because shake table test systems are eventually nonlinear by nature. In addition, interaction between the table and specimen could affect the control accuracy of shake table testing significantly. Various novel control algorithms have been proposed to improve the control accuracy of shake table testing; however, reference values for control performance assessment remain rare. In this study, reference values for control performance assessment of shake table testing are specified based on the statistical analyses of 1,209 experimental data provided by the Seismic Simulator Laboratory of National Center for Research on Earthquake Engineering in Taiwan. Three individual reference values are considered for the assessment including the root-mean-square error of the achieved acceleration time history; the percentage of the spectral acceleration that exceeds the determined tolerance range over the frequency of interest; and the error-ratio of the achieved peak ground acceleration. Quartiles of the real experimental data in terms of the three objective variables are obtained, providing users with solid and simple references to evaluate the control performance of shake table testing. Finally, a set of experimental data of a newly developed control framework implementation for uni-axial shake tables are used as an application example to demonstrate the significant improvement of control accuracy according to the reference values provided in this study.

• Nutrition Research and Practice
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• v.16 no.sup1
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• pp.57-69
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• 2022

BACKGROUND/OBJECTIVES: Vitamin D is produced in the skin during sun exposure and is also ingested from foods. The role of vitamin D needs to be considered in the prevention and management of various diseases. Moreover, since the majority of Koreans spend their days indoors, becoming susceptible to the risk of vitamin D deficiency. The current study aims to prepare a basis for determining dietary reference intake of vitamin D in Korea, by reviewing the evidence against various diseases and risks. MATERIALS/METHODS: Literature published in Korea and other countries between 2014 and 2018 was prioritized based on their study design and other criteria, and evaluated using the RoB 2.0 assessment form and United States Department of Agriculture Nutrition Evidence Library Conclusion Statement Evaluation Criteria. RESULTS: Of the 1,709 studies, 128 studies were included in the final systematic analysis after screening. To set the dietary reference intakes of vitamin D based on the selected articles, blood 25(OH)D levels and indicators of bone health were used collectively. Blood vitamin D levels and ultraviolet (UV) exposure time derived from the Korean National Health and Nutrition Examination Survey were analyzed to establish the dietary reference intakes of vitamin D for each stage of the life cycle. The adequate intake levels of vitamin D, according to age and gender, were determined to be in the range of 5-15 ㎍/day, and the tolerable upper intake level was established at 25-100 ㎍/day. CONCLUSIONS: The most important variable for vitamin D nutrition is lifestyle. A balanced diet comprising foods with high contents of vitamin D is important, as is vitamin D synthesis after UV exposure. The adequate intake level of vitamin D mentioned in the 2015 Dietary Reference Intakes for Korean (KDRI) remained unchanged in the 2020 KDRI for the management of vitamin D nutrition in Koreans.