• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.11
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• pp.81-86
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• 2004

Hybrid beamformer composed of Direction-of-Arrival (DOA) based scheme followed by Maximal Ratio Combining (MRC) is proposed to overcome the degradation due to inaccurate channel estimation caused by insufficient pilot power, which happens in conventional Single-Input Multiple-Output (SIMO) Code Division Multiple Access (CDMA) reverse link. The proposed scheme could provide more accurate channel estimation and interference reduction at the expense of diversity gam in the spatially correlated SIMO channel. As a result, hybrid scheme outperforms conventional MRC beamformer for six or more antennas in the channel environment, in which Angle-of-Spread (AOS) is within 30$^{\circ}$.

• Journal of Fashion Business
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• v.15 no.1
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• pp.50-62
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• 2011

The purpose of this study is to catch the difference for the appraisal standard of a product which the adult women's consumers think importantly when they purchase the clothing made of organic cotton and the appraisal standard according to the demographic characteristics. The data collection for research was done for the women in from their 20's to 50's who are living in the regions of Gyungnam, Busan, Ulsan in Korea. The copies of the used questionnaire were 622 copies. To analyze the collected data, ${\chi}^2$-test, t-test, Cronbach's ${\alpha}$ test, ANOVA, Duncan test were carried out by SPSS 14.0. As the analysis result of data, the appraisal standard for purchasing the clothing made of organic cotton was classified with the five factors. The appraisal standard which the adult women's consumers think importantly when they purchase the clothing made of organic cotton showed the significant difference according to the demographic characteristics. The ratio for post-purchase dissatisfaction showed higher than the one for satisfaction. The dissatisfaction showed the significant difference according to the demographic characteristics. The dissatisfaction for a high price, color and insufficient design showed a relatively high ratio.

• Journal of Nutrition and Health
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• v.32 no.7
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• pp.812-820
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• 1999

The aim of this investigation was to assess the difference of health behaviors, dietary patterns and nutrient intakes between smokers and nonsmoker from 435 free living elderly in Kyunggi province. The study subjects were interviewed to collect general characteristics and health behaviors such as smoking, exercise, alcohol consumption, and food habits by questionnaires and nutrient intakes by a 24-hour recall, and weight, height, waist, hip, and blood pressure were measured. The percentages of smoker were 52.3% in males and 12.1% in females. Current smokers were fond of alcohol, salty or hot food, tended to have meals irregularly and insufficient sleep, and were inactive lifestyle compared to nonsmokers. Smokers consumed fewer servings of vegetables, fruits, and beans and their products. Women who smoked consumed less energy, carbohydrates, and vitamin E than nonsmokers, and their nutrient adequacy ratio of protein, iron, phosphate, niacin, vitamin B1, and vitamin C were significantly lower than nonsmokers. There were no differences of nutrient intakes and nutrient adequacy ratio between smokers and nonsmokers in male subjects. In conclusion, elderly smokers tended to have less healthy life style, food habit, and dietary nutrient intakes which may influence the deleterious effects of smoke components on cancer and coronary heart disease risk, thus health education program should include nutrition education as well as smoking cessation.

• Journal of Navigation and Port Research
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• v.43 no.6
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• pp.450-461
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• 2019

According to the results of the management evaluation of the nation's public firms over the past seven years, the rating of the port corporation is generally insufficient. According to the results of the seven-year study 2011-2017, the average debt ratio of the port corporation was 34.5%, two to three times lower than that of the general public company, the operating profit ratio of sales was three times higher, and the value added per person was 1.6-1.9 times better. However, the aggregate score and grade were generally low, with 4.1% of the total number of employees of the general public corporation, 10% of the average total assets, and 1% of the average sales volume. The distributed analysis results and panel return analysis results show that the size significantly impacts the overall score and grade. Additionally, major business standards such as port volume, not controlled by the port corporation, appear to have a decisive influence on the low grade of the port corporation. Thus, it appears that improvement and supplementation of key business indicators of port construction are urgently needed in the management evaluation system, which can be properly controlled.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.05a
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• pp.922-924
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• 2015

Recently, the image processing technologies using the public media such as the film, TV, camera and advertisement have been rapidly developed. However, the deterioration occurs with the image in the process of data processing, transmission and storage, and the typical cause of such deterioration is the salt and pepper noise. Typical filters to remove the salt and pepper noise include CWMF(center weighted median filter) and AMF(adaptive median filter) but such filters bring more or less insufficient characteristics of noise removal and visual error as the noise density gets higher. Thus, this paper proposed the median filter which applied the local mask segmented to 4 areas in order to remove the salt and pepper noise effectively and used PSNR(peak signal to noise ratio) as a criterion of judgment.

• Phonetics and Speech Sciences
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• v.5 no.4
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• pp.17-24
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• 2013

This study is aimed at finding out different types of speech characteristics categorized based on voice rehabilitation techniques used on twenty-six patients (all-male) with total or partial laryngectomees. The speech intelligibility of standard esophageal (SE), tracheoesophageal speech (TE), and electriclarynx (EL) was measured by using the CSL and eleven listeners were instructed to rate the speech on a 5-point scale. The vowel space parameters such as vowel space, VAI, FCR, and F2 ratio were measured by averaging 5 repeats of each vowel (/a/, /e/, /i/, /u/) and the results were put into the parameter formula. The results showed significant statistical differences in speech intelligibility and vowel space between SE and TE. The speech intelligibility and vowel space of TE were higher than those of SE or EL and there was a high correlation between speech intelligibility and some parameters (vowel space, VAI, F2 ratio). The results also showed that TE's speech characteristics were most similar to normal groups comparing with SE and EL, but still very deviant in laryngeal speech. This was due to insufficient airflow intake into the esophagus when producing sounds, and because articulation movement was carried out differently among groups. Therefore, these findings will contribute to establishing a baseline related to speech characteristics in voice rehabilitation for patients with alaryngeal speech.

• Journal of Korean Association for Spatial Structures
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• v.8 no.2
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• pp.95-103
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• 2008

This paper is concerned with the damping ratios of two methods, which are frequency domain and time domain approach. Ambient vibrations and synchronized human excitation test were conducted to three reinforced concrete buildings ranging from eleven to nineteen stories. The performance of the half power bandwidth method was investigated using three kinds of sample size, 1024, 2048, and 4096. The damping ratio by synchronized human excitation ranges from 1.05% to 1.22% in the long direction and from 1.16% to 1.50% in short direction. Damping by half power bandwidth method is slightly more overestimated than the synchronized human excitation due to insufficient record length. Damping evaluation by half power bandwidth method was found to be enhanced by using the narrower bandwidth with long recorded data.

• Phonetics and Speech Sciences
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• v.8 no.2
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• pp.73-80
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• 2016

The purpose of this study was to analyze perceptual and spectral/cepstral measurements in patients with adductor spasmodic dysphonia(ADSD). Sixty participants with gender and age matched individuals(30 ADSD and 30 controls) were recorded in reading a sentence and sustained the vowel /a/. Acoustic data were analyzed acoustically by measuring CPP, L/H ratio, mean CPP F0 and CSID, and auditory-perceptual ratings were measured using GRBAS. The main results can be summarized as below: (a) the CSID for the connected speech was significantly higher than for the sustained vowel (b) the G, R and S for the connected speech were significantly higher than for the sustained vowel (c) Spectral/cepstral parameters were significantly correlated with the perceptual parameters, and (d) the ROC analysis showed that the threshold of 13.491 for the CSID achieved a good classification for ADSD, with 86.7% sensitivity and 96.7% specificity. Spectral and cepstral analysis for the connected speech is especially meaningful on cases where perceptual analysis and clinical evaluation alone are insufficient.

• 한국연소학회:학술대회논문집
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• 2012.04a
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• pp.7-8
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• 2012

The effects of interaction between partially premixed and premixed swirl flames on CO and NOx emissions were experimentally investigated using a hybrid/dual swirl jet combustor for a micro-gas turbine. Under the condition of constant angle ($45^{\circ}$) for outer swirl vane, the angle and direction of inner swirl vane installed for a partially premixed flame were varied as main parameters with a constant fuel flow rate for each nozzle. It was found that for all conditions, CO and NOx emissions were measured below 4 ppm and 15 ppm at 15% $O_2$, respectively, in a wide range of equivalence ratio (0.6~0.9). For co-swirl flows, CO emission increased dramatically as the angle of inner swirl vane increased from $15^{\circ}$ to $45^{\circ}$ near lean-flammability limit (i.e. equivalence ratio of 0.5). On the other hand, the case of swirl $angle=45^{\circ}$ provided the lowest NOx emission at higher equivalence ratios than 0.6. For counter-swirl flows, the case of swirl $angle=45^{\circ}$ extended the lean-flammability limit but higher NOx emissions were found compared to those of co-swirl flows. These results could be inferred by interaction between (inner) partially premixed and (outer) premixed swirl flames. However, these estimations were not clear yet because there was insufficient data on turbulent flow structure and fuel-air mixing in the present experimental approach.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.61-65
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• 2003

Bottom ash among the coal ash is not used because of its poor properties. But encouraging the use of bottom ash as a construction material is a sensible method of utilization as it avoids the problems and costs associated with disposal and provides an alternative aggregate source. This study was aimed at using bottom ash as an alternative fine aggregate source to provide a solution to disposal and insufficient fine aggregate for the production of concrete. So properties of domestic bottom ash were estimated due to the difference of each domestic bottom ash. And compressive strength and durability were estimated as basic data to use bottom ash in building industries. As a result of the experiment, the very porous surface and angular shape of the bottom ash particles necessitate a higher apparent water-cement ratio. And due to the higher water requirement, the compressive strength and durability of mortar is lower than those of the control samples. But when 25 percent of the total dry weight of the natural fine aggregate was replaced by bottom ash, the engineering characteristics were similar.