• The Korean Journal of Applied Statistics
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• v.23 no.6
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• pp.997-1021
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• 2010

This paper compares the two most widely used seasonal adjustment methods: the X-12-ARIMA and TRAMO-SEATS procedures. The basic features of these methods are discussed and compared in both their theoretical and empirical aspects. In doing so, the X-13A-S program is used to reevaluate their applicability to Korean macroeconomic data by considering possible structural breaks in the series. The finding is that both methods provide very reliable and stable estimates of seasonal factors and seasonally adjusted data. As for the empirical comparisons, TRAMO-SEATS appears to outperform X-12-ARIMA, although the results are somewhat mixed depending on the comparison criteria used and on the series under analysis. In particular, the performance of TRAMO-SEATS turns out to compare more favorably when seasonal adjustment is carried out to each sub-samples (by taking possible structural breaks into account) than when the whole sample period is used. The result suggests that as the model-based TRAMO-SEATS has a considerable theoretical appeal, some features of TRAMO-SEATS should further be incorporated into X-12-ARIMA until a standard and integrated procedure is reached by combining the theoretical coherence of TRAMO-SEATS and the empirical usefulness of X-12-ARIMA.

• Biomedical Science Letters
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• v.12 no.1
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• pp.23-27
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• 2006

The rate of metallothionein synthesis on cadmium-poisoned rats reflects the level of toxicity, and also it reduces the toxicity which is caused by the uptake of cadmium. Chlorella supplementation in the diets of the cadmium-poisoned rats decreased the concentration of cadmium in blood and urine compared with the control group. Although the liver and kidneys of rats are major target organs of cadmium and coherence of metallothionein and cadmium, no previous study has determined the correlation between the rate of metallothionein synthesis in the liver and kidneys of rats and dietary supplementation of chlorella with cadmium uptake. This study analyzed total metallothionein level on the tissue of the liver and kidneys, the concentration of cadmium bound to the metallothionein, and the total concentration of cadmium on the tissue of the liver and kidneys after dietary supplementation with 1%, 5%, and 10% dried chlorella and 40 ppm of cadmium to 46 male SD rats (mean weight: $150\pm20\;g$) for 4 weeks. According to the data analysis of the total rate of metallothionein synthesis in the liver and kidneys, the group of SD rats on the supplementation with 1% chlorella and 40 ppm of cadmium showed a rate of $93.2\pm8.9\;ng/g$, a significant decrease of 58.8% compared to that of the control group of SD rats on the supplementation with cadmium only, which showed a rate of $227.3\pm32.5 ng/g$ (P=0.0001). In contrast, no significant difference was observed through the changing of chlorella concentrations between 5% and 10% chlorella supplementation with cadmium. The group supplemented with 1% or greater chlorella levels represented a greater decrease in the total cadmium concentration of the kidney and liver tissues, the amount of total metallothionein synthesis, the amount of metallothionein with binding to cadmium, and the concentration of free cadmium without binding to metallothionein. Consequently, the supplementation of 1% and 5% chlorella was effective in reducing the synthesis of metallothionein for cadmium uptake, but increased the rate of binding of cadmium to metallothionein.

• Journal of Microbiology and Biotechnology
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• v.23 no.5
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• pp.644-651
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• 2013

The fermented manure derivative known as Preparation 500 is traditionally used as a field spray in biodynamic agriculture for maintaining and increasing soil fertility. This work aimed at characterizing the product from a microbiological standpoint and at assaying its bioactive properties. The approach involved molecular taxonomical characterization of the culturable microbial community; ARISA fingerprints of the total bacteria and fungal communities; chemical elemental macronutrient analysis via a combustion analyzer; activity assays for six key enzymes; bioassays for bacterial quorum sensing and chitolipooligosaccharide production; and plant hormone-like activity. The material was found to harbor a bacterial community of $2.38{\times}10^8$ CFU/g dw dominated by Gram-positives with minor instances of Actinobacteria and Gammaproteobacteria. ARISA showed a coherence of bacterial assemblages in different preparation lots of the same year in spite of geographic origin. Enzymatic activities showed elevated values of ${\beta}$-glucosidase, alkaline phosphatase, chitinase, and esterase. The preparation had no quorum sensing-detectable signal, and no rhizobial nod gene-inducing properties, but displayed a strong auxin-like effect on plants. Enzymatic analyses indicated a bioactive potential in the fertility and nutrient cycling contexts. The IAA activity and microbial degradation products qualify for a possible activity as soil biostimulants. Quantitative details and possible modes of action are discussed.

• Korean Journal of Optics and Photonics
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• v.14 no.5
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• pp.483-490
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• 2003

We have analyzed theoretically optical pulse propagation in a coherent atomic medium for amplification without inversion (AWI), which is achieved by adding incoherent optical pumping to a typical EIT system. In order to explain experimental results [Kim et al., J. Phys. B, 36, 2671(2003)] to control the group velocity of the optical pulse by changing pumping power, we established a 5-level atomic system and applied density matrix equations. This AWI model system is different from previous AWI systems from the viewpoint of using two levels for incoherent optical pumping isolated optically from the EIT (electromagentically induced transparency) system so that more atoms can participate in pulse speed control. We have found that population transfer by collisions between ground states plays a decisive role for efficient AWI, and more atoms are effective for slowing the pulse. Our numerical results are in good agreement qualitatively with experimental results.

• Journal of the Korean Chemical Society
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• v.58 no.6
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• pp.580-589
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• 2014

The concepts used to explain specific phenomenon can be influenced by context or coherent regardless of context. The purpose of this study is to understand middle school students' concept of particles in particular context and to investigate the effects of context on concept of particles. A conceptual questionnaire was developed to find out how students represented particles in two contexts: solid and solution states of electrolytes, and ion precipitation reaction. The questionnaire was administered to $9^{th}$ grade students after classes of 'electrolyte and ions' unit. The responses of students were analyzed using framework developed for categorization of students' concepts. The results are as follows: First, it was found that students used various concepts on particles when they explained solid and solution state of electrolytes, respectively. Second, we identified students' concepts of particles used to explain ion precipitation reaction. In addition, we recognized that majority of students failed to write correct chemical symbols. Third, approximately 79% of students showed coherent responses for explanation of particles in solution state of both electrolytes and ion precipitation reaction. About 57% of students had scientific concepts. Some suggestions were made based on results for acquisition of scientific concepts on particles in different contexts.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.167-174
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• 2016

One of the major causes of morbidity and mortality in breast cancer patients is delay in seeking help. Leventhal's self-regulation model provides an appropriate framework to assess delay in seeking help. The aim of this study was to investigate the relationship between "illness perception" and "help seeking delay" in breast cancer patients based on Leventhal's self-regulation model. In this correlational descriptive study with convenience sampling conducted in 2013, participants were 120 women with breast cancer who were diagnosed in the last year and referred to chemotherapy and radiotherapy centers in Rasht, Iran. Data collection scales included demographic data, Revised Illness Perception Questionnaire (IPQ-R)and a researcher made questionnaire to measure the delay in seeking help. Pre-hospital delay (help seeking delay) was evaluated in 3 phases (assessment, disease, behavior). The data were analyzed using SPSS-19. The mean (SD) age calculated for the patients was $47.3{\pm}10.2$. Some 43% of the patients had a high school or higher education level and 82% were married. The "pre-hospital delay" was reported ${\geq}3months$. Logistic regression analysis showed that none of the illness perception components were correlated with appraisal and behavioral delay phases. In the illness delay phase, "time line" (p-value =0.04) and "risk factors"(p-value=0.03) had significant effects on reducing and "psychological attributions" had significant effects on increasing the delay (p-value =0.01). "Illness coherence" was correlated with decreased pre-hospital patient delay (p-value<0.01). Women's perceptions of breast cancer influences delay in seeking help. In addition to verifying the validity of Leventhal's self-regulation model in explaining delay in seeking help, the results signify the importance of the "illness delay phase" (decision to seek help) and educational interventions-counseling for women in the community.

• Korean Journal of Remote Sensing
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• v.31 no.2
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• pp.111-125
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• 2015

In this study, the target detection using both high-resolution satellite SAR and Elecro-Optical (EO) images such as TerraSAR-X and WorldView-2 is performed, considering the characteristics of targets. The targets of our interest are featured by being stationary and appearing as cluster targets. After the target detection of SAR image by using Constant False Alarm Rate (CFAR) algorithm, a series of processes is performed in order to reduce false alarms, including pixel clustering, network clustering and coherence analysis. We extend further our algorithm by adopting the fast and effective ellipse detection in EO image using randomized hough transform, which is significantly reducing the number of false alarms. The performance of proposed algorithm has been tested and analyzed on TerraSAR-X SAR and WordView-2 EO images. As a result, the average false alarm for group of targets is 1.8 groups/$64km^2$ and the false alarms of single target range from 0.03 to 0.3 targets/$km^2$. The results show that groups of targets are successfully identified with very low false alarms.

• Economic and Environmental Geology
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• v.53 no.4
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• pp.479-489
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• 2020

A fault is a geological structure that can be a migration path or a cap rock of hydrocarbon such as oil and gas, formed from source rock. The fault is one of the main targets of seismic exploration to find reservoirs in which hydrocarbon have accumulated. However, conventional fault detection methods using lateral discontinuity in seismic data such as semblance, coherence, variance, gradient magnitude and fault likelihood, have problem that professional interpreters have to invest lots of time and computational costs. Therefore, many researchers are conducting various studies to save computational costs and time for fault interpretation, and machine learning technologies attracted attention recently. Among various machine learning technologies, many researchers are conducting fault interpretation studies using the support vector machine, multi-layer perceptron, deep neural networks and convolutional neural networks algorithms. Especially, researchers use not only their own convolution networks but also proven networks in image processing to predict fault locations and fault information such as strike and dip. In this paper, by investigating and analyzing these studies, we found that the convolutional neural networks based on the U-Net from image processing is the most effective one for fault detection and interpretation. Further studies can expect better results from fault detection and interpretation using the convolutional neural networks along with transfer learning and data augmentation.

• Journal of the Korean Home Economics Association
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• v.39 no.12
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• pp.1-14
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• 2001

The purpose of this study was to analyze the current states of interior design as a major at vocational high schools and to suggest ways in which it can be improved. Three hundred and four students and twelve teachers of two vocational high schools comprised the sample population for this study. Data was collected using two methods, questionnaires and interviews. Frequency distribution, mean, and chi-square tests were used to analyze the data. The findings of this study are as follows: The student respondents were more interested in studying residential design, furniture design and making, drafting and perspective drawing than other areas of study. Most teachers had difficulties teaching the subject of residential design because they were not well educated with this area. Surprisingly most students hoped to extend their education to a university or college after graduation, not to enter the workforce. According to teachers'responses, almost ninety percentage of students entered university or college. And more than two thirds of the students desired to study an interior design related major at the university level. Among graduates having jobs, half of them were working in interior design fields. If the students had to choose their jobs, they would work in interior design fields. The variables differentiating several related careers after graduation were school, grade, and sex. The students viewed interior design, interior coordination, and CAD related work as fields likely to enter upon graduating from vocational high schools; however, teachers viewed furniture making, interior accessorizing, and home fashion as fields more appropriate to the students'level of training. The teacher respondents criticized the textbooks in four categories; suitability with the students'level was average or below average; students'interest level and students'understanding level were average or above average; and whether the book was easy or difficult to be utilized for the purposes of teaching was also average or above average. The criticism was a little diverse depending on each book or each chapter. The teachers pointed out several problems using those books, such as insufficient examples or explanation, lack of coherence between some chapters, and an incompatibility with the allotted time frame in class. The merits of the textbooks varied such as a well organized structure, ability to generate students'interest. This study revealed that the strategy for improving the interior design major at vocational high schools should invoke, 1) dividing students into two groups-one to enter a university; the other to have jobs after graduation to focus their interests. 2) improving textbooks more appropriate to the students. 3) providing present teachers the opportunities for in-service training and hiring new teachers with credentials more suitable to educate students who desire to be interior designers.

• The Journal of the Acoustical Society of Korea
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• v.32 no.2
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• pp.95-103
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• 2013

An underwater acoustic (UWA) communication in shallow water is strongly affected by the water surface and the seabed acoustical properties. Every reflected signal to receiver experiences a time-variant scattering in sea surface roughness and a grazing-angle-dependent reflection loss in bottom. Consequently, the performance of UWA communication systems is degraded, and high-speed digital communication is disrupted. If there is a dominant signal path such as a direct path, the received signal is modeled statistically as Rice fading but if not, it is modeled as Rayleigh fading. However, it has been known to be very difficult to reproduce the statistical estimation by real experimental evaluation in the sea. To give an insight for this scattering and grazing-angle-dependent bottom reflection loss effect in UWA communication, authors conduct experiments to quantify these effects. The image is transmitted using binary frequency shift keying (BFSK) modulation. The quality of the received image is shown to be affected by water surface scattering and grazing-angle-dependent bottom reflection loss. The analysis is based on the transmitter to receiver range and the receiver depth dependent image quality and bit error rate (BER). The results show that the received image quality is highly dependent on the transmitter-receiver range and receiver depth which characterizes the channel coherence bandwidth.