• KIEAE Journal
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• v.16 no.2
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• pp.17-22
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• 2016

Purpose: Sensitivity analysis offers a good guideline for designing energy conscious buildings, which is fitted to a specific building configuration. Sensitivity analysis is, however, still too expensive to be a part of regular design process. The One-at-a-time (OAT) is the most common and simplest sensitivity analysis method. This study aims to propose a reasonable ground that the OAT can be an alternative method for the variance-based method in some early design scenarios, while the variance-based method is known adequate for dealing with nonlinear response and the effect of interactions between input variables, which are most cases in building energy simulations. Method: A test model representing the early design phase is built in the DOE2 energy simulations. Then sensitivity ranks between the OAT and the Variance-based methods are compared at three U.S. sites. Result: Parameters in the upper rank by the OAT do not much differ from those by the Main effect index. Considering design practices that designers would chose the most energy saving design option first, this rank similarity between two methods seems to be acceptable in the early design phase.

• Integrative Medicine Research
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• v.7 no.2
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• pp.136-140
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• 2018

Background: The Sasang constitutional analysis tool (SCAT) is an integrated Sasang constitutional analysis system developed by the Korea Institute of Oriental Medicine. This study aimed to evaluate the reliability of a questionnaire for measuring personality and pathophysiological symptoms that is one of the components of the SCAT. Methods: In this study, data were collected from university students in their twenties. Tests were administered twice, with an interval of 4 weeks between tests. Test-retest data from 176 students were collected and used for analysis. Internal consistency reliability was analyzed by using Cronbach's alpha coefficient, and test-retest reliability was analyzed by using Spearman's rank correlation coefficient. Results: Cronbach's alpha coefficient was 0.788 for personality, 0.511 for eating habits, 0.718 for digestion, 0.667 for heat- or cold-wise penchant, and 0.612 for water ingestion. Spearman's rank correlation coefficients, which were used to assess correlations between test and retest results, ranged from 0.444 to 0.828. Conclusion: The internal consistency and test-retest reliability of the SCAT questionnaire were found to be satisfactory.

• Journal of Environmental Health Sciences
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• v.42 no.6
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• pp.419-429
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• 2016

Objectives: According to the new Chemical Control Act from the Korean Ministry of Environment (2014-259), workers handling hazardous chemicals should wear personal protective equipment (PPE). However the act simply states in basic phrases that every worker handling one or more of the 69 listed chemicals should wear PPE and does not consider the unique hazard characteristics of chemicals and work types. The main purpose of this study is to provide basic data to revise the act to suit particular work processes and situations. Methods: The hazard rank of the substances was classified based on hazardous characteristics such as LC50 and vapor pressure using matrix analysis. The workplace exposure risk of the substances was also determined through a matrix analysis based on the previously determined hazard ranks and the demands of manual handling together with the likelihood of accident frequency of the operation combined with the exposure of workers during spill accidents. Results: To meet the demands for developing subsequent guidelines for the risk-based application of PPE in hazardous workplaces, this study sorted the 69 listed chemicals into five hazardous categories based on their LC50 and vapor pressures, and also assigned exposure categories according to exposure vulnerability for various types of work which are frequently performed throughout the life cycle of the chemicals. Conclusion: In the next study, an exposure risk matrix will be produced using the hazard rank of chemicals and workplace exposure risk, and then PPE will be selected to suit the categories of the exposure risk matrix.

• Korean Chemical Engineering Research
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• v.50 no.6
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• pp.1086-1092
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• 2012

In this study, kinetic studies and analysis of the produced syngas were conducted for low rank coal gasification under $CO_2$ atmosphere. 6 coals were analyzed to measure amount of sulfur and ash by proximate and ultimate analyses. And then they were analyzed to select suitable sample by using Thermogravimetric analyzer (TGA). Selected coal sample Samhwa was mixed with catalysts. Mixed samples with catalysts were used to get activation energy under $CO_2$ atmosphere by using Kissinger's method and shrinking core model (SCM). Also, analysis of produced syngas was performed by Gas Chromatography (GC). In this experiment, activation of the $K_2CO_3$ was the best performance, and result of the analysis of the syngas showed similar trend with result of the activation energy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.6
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• pp.633-641
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• 2020

Residential complexes offer a sense of community and convenience, but making closed and privated space have been criticized.Closed urban spaces have issues encouraging residential segregation.large apartment complexes over 1,000 households,the most poular housing type in Korea, seems to make urban space more closed and privated than ever before. Our study puts forward and tests the hypothesis that large apartment complexes with over 1,000 households are linked to residential segregation. First of all, we examined the degree of residential segregation of metropolitan cities in Korea over a nine-year period (2011-2019). The dissimilarity index and the delta index were used for determining the extent of residential segregation. Next, we tested our hypothesis by Spearman's rank correlation analysis. Spearman's rank correlation analysis was performed on the residential segregation index per administrative division ("dong") and the number of large apartment complexes per administrative division ("dong").

• Journal of Korean Academy of Nursing Administration
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• v.13 no.1
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• pp.98-108
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• 2007

Purpose: The objective of this research was to explore the levels of patient satisfaction and job satisfaction according to the level of nurse manpower, in order to provide effective management for nurses. Methods: The research was conducted from November 1 to December 30, 2006, with a survey of 310 nurses and 240 patients at eight tertiary hospitals in Seoul. Data were collected according to the level of nurse manpower from the first (a nurse vs. patient ratio of below 2.0) to the sixth (a ratio of over 4.0) rank. The survey tools were used Park-Yoon's job satisfaction (1992) and Wandelt and Ager (1974)'s patient satisfaction. The acquired data were analyzed with SPSS $PC^+$ 12.0 program using descriptive methods, ${\chi}^2$ test, ANCOVA, and Scheffe. Results: Overall job satisfaction of nurses showed 3.10 and patient satisfaction of patients showed 4.15. Analysis based on the level of nurse manpower showed that hospitals of first and second rank had higher scores than those of lower rank for nurse's job satisfaction and patient satisfaction. Conclusion: Hospitals with a higher level of nurse manpower showed higher score of nurse's job satisfaction and patient satisfaction.

• Genomics & Informatics
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• v.1 no.2
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• pp.94-100
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• 2003

Motivation: Many have observed a nonlinear relationship between the signal intensity and the transcript abundance in microarray data. The first step in analyzing the data is to normalize it properly, and this should include a correction for the nonlinearity. The commonly used linear normalization schemes do not address this problem. Results: Nonlinearity is present in both cDNA and oligonucleotide arrays, but we concentrate on the latter in this paper. Across a set of chips, we identify those genes whose within-chip ranks are relatively constant compared to other genes of similar intensity. For each gene, we compute the sum of the squares of the differences in its within-chip ranks between every pair of chips as our statistic and we select a small fraction of the genes with the minimal changes in ranks at each intensity level. These genes are most likely to be non-differentially expressed and are subsequently used in the normalization procedure. This method is a generalization of the rank-invariant normalization (Li and Wong, 2001), using all available chips rather than two at a time to gather more information, while using the chip that is least likely to be affected by nonlinear effects as the reference chip. The assumption in our method is that there are at least a small number of non­differentially expressed genes across the intensity range. The normalized expression values can be substantially different from the unnormalized values and may result in altered down-stream analysis.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.1
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• pp.96-99
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• 2016

Generally, bistatic clutter, contrary to the monostatic clutter, has nonlinear structure in Angle-Doppler domain due to the noncooperative motion of the transmitter and the receiver. In this paper, we first simulate the bistatic clutter structure resulting from the relative motion of the transmitter and the receiver and then analyze their relations through the bistatic clutter structure in Angle-Doppler domain. Also, we show the operation condition of the transmitter and the receiver leading to low rank of a covariance matrix of the bistatic clutter.

• Journal of Information Processing Systems
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• v.13 no.4
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• pp.987-999
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• 2017

Extraction of influential people from their respective domains has attained the attention of scholastic community during current epoch. This study introduces an innovative interaction strength metric for retrieval of the most influential users in the online social network. The interactive strength is measured by three factors, namely re-tweet strength, commencing intensity and mentioning density. In this article, we design a novel algorithm called IPRank that considers the communications from perspectives of followers and followees in order to mine and rank the most influential people based on proposed interaction strength metric. We conducted extensive experiments to evaluate the strength and rank of each user in the micro-blog network. The comparative analysis validates that IPRank discovered high ranked people in terms of interaction strength. While the prior algorithm placed some low influenced people at high rank. The proposed model uncovers influential people due to inclusion of a novel interaction strength metric that improves results significantly in contrast with prior algorithm.

• Journal of the Korea Society of Computer and Information
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• v.11 no.4 s.42
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• pp.9-15
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• 2006

In this paper we propose Wilcoxon test, Median test and Van der Waerden test such as linear rank tests in two-sample location problem for detecting edges effectively in noisy images. These methods are based on detecting image intensity changes between two pixel neighborhoods using an edge-height model to perform effectively on noisy images. The neighborhood size used here is small and its shape is varied adaptively according to edge orientations. We compare and analysis the performance of these statistical edge detectors on both natural images and synthetic images with and without noise.