• Journal of the Korean Society of Combustion
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• v.5 no.1
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• pp.19-30
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• 2000

The characteristics of NOx emissions in pure hydrogen nonpremixed flames with coaxial air are analyzed numerically for the three model cases of coaxial air flames classified by varying coaxial air velocity and/or fuel velocity. In coaxial air flames, the flame length is reduced by coaxial air and can be represented as a function of the ratio of coaxial air to fuel velocity. Coaxial air decreases flame reaction zone, resulting in reducing flame residence time significantly. Finally, the large reduction of EINOx is achieved by the decrease of the flame residence time. It is found that because coaxial air can break down the flame self-similarity law, appropriate scaling parameters, which are different from those in the simple jet flames, are recommended. In coaxial air flames, the flame residence time based on the flame volume produces better results than that based on a cube of the flame length. And some portion of deviations from the 1/2 scaling law by coaxial air may be due to the violation of the linear relationship between the flame volume and the flame reaction zone.

• Journal of Korean Society of Rural Planning
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• v.16 no.4
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• pp.13-22
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• 2010

Rural landscape is an outcome of residents' life activity based on natural environment. Unlike city, rural residents make their own landscape over a period of time interacting with nature through cultivating and building houses and huts based on the background. Therefore, residents' role in rural area is of greater importance than city's and their recognition of landscape is a key factor to evaluate and manage rural landscape. Landscape Evaluation Map which utilizing Feeling Map method is a evaluation tool to [md out residents' recognition of landscape. In this tool, responses evaluate landscape around their living space and mark color dots which mean landscape grade on a map. This research is to examine effectiveness and applicability of the tool, Landscape Evaluation Map, which is recommended to estimate residents' evaluation of landscape. Through analyzing 7 cases of field application, the effectiveness of Landscape Evaluation Map has been verified and also demerits have been drawn. After modifying detailed techniques and developing resident education, Landscape evaluation map could be applied to [md out landscape resources rather than to evaluate whole rural landscape.

• Korean Journal of Veterinary Research
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• v.34 no.1
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• pp.93-97
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• 1994

A immunological survey of paratuberculosis in dairy and Korean native cattles was conducted by enzyme linked immunosorbent assay(ELISA), complement fixation test(CFT), agar gel immunodiffusion test (AGID) and intradermal skin test(ID). Over all prevalence of pararuberculosis in cattles was 6.7%(109/1633) by ID, 7.5(205/2719) by AGID, 9.3% (245/2641) by CFT and 13.4%(363/2719) by ELISA. Prevalence in dairy cattle was higher than that of Korean native cattle. Of 70 ELISA-positive cattle, 23(28.6%) and 48(68.6%) cattles were classified as positive in the AGID and positive or suspect in CFT, respectively. Of 92 ELISA-suspect cattle, 32(34.9%) and 48(52.2%) cattles were classified as AGID-positive and CFT-positive or suspect, respectively. It was concluded that paratuberculosis is widespread in cattle of Korea.

• Journal of Broadcast Engineering
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• v.18 no.5
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• pp.771-774
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• 2013

This study investigates the relationship between voice quality measurements and emotional states, in addition to conventional prosodic and cepstral features. Open quotient, harmonics-to-noise ratio, spectral tilt, spectral sharpness, and band energy were analyzed as voice quality features, and prosodic features related to fundamental frequency and energy are also examined. ANOVA tests and Sequential Forward Selection are used to evaluate significance and verify performance. Classification experiments show that using the proposed features increases overall accuracy, and in particular, errors between happy and angry decrease. Results also show that adding voice quality features to conventional cepstral features leads to increase in performance.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05c
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• pp.221-224
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• 2001

In connection with the monitoring of insulation degradation of large power apparatus in order to predict their unexpected service failures, a statistical treatment, such as phase resolved partial discharge analysis(PRPDA), has been established for the on-line monitoring system during the past decades. However, this method has shown some inconveniences to distinguish the nature of the PD source in power apparatus. In this regard, a novel approach based on the chaotic analysis(CAPD) is proposed describing the fundamental ideas, outcomes and different view points from conventional PRPDA. In order to make a model for the possible defects causing sudden failures in service, several types of specimen were prepared. And partial discharge signals, originated from those samples, were measured and analysed by means of PRPDA and CAPD respectively. Throughout this paper, it seems that the correlation between the consecutive PD pulses depending on the nature of PD could be investigated by CAPD. Therefore, it could be considered that the nature of PD source can be distinguished more distinctively when the PRPDA is combined with CAPD.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.15 no.1
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• pp.276-284
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• 2002

Aromatherapy is becoming increasingly popular, however there are few clear indications for its use. To systematically review the clinical studies on aromatherapy, computcrized literature searches were performed from PubMed. Fourteen trials were located. The conclusions were as follows: 1. All the trials were published after 1993. 2. To analyze the publication journals, five of fourteen trials were on nursing, three of them on neuropsychiatry and one on dermatology. 3. Most widely used indications of aromatherapy were on general physical, psychological and physiological field. 4. On the procedure of aromatherapy, eight of them were by massage, three by inhalation, one by massage & inhalation and one by bath additive. 5. To analyze the publication type, all fourteen trials were clinical trials. Twelve of them were randomized controlled trials. Two of them were using single subject design. 6. To observe the sample size, five of them were under 10, four from 10 to 50, two from 50 to 100 and three above 100. 7. Eleven of fourteen trials were using inferential statistics. Eight of the eleven trials were significantly effective, but three had no statistical significance.

• The Journal of the Acoustical Society of Korea
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• v.31 no.6
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• pp.353-358
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• 2012

This paper describes acoustic phonetic parameters for detecting nasal place in a knowledge-based speech recognition system. Initial acoustic phonetic parameters are selected by studying nasal production mechanisms which are radiation of the sound through the nasal cavity. Nasals are produced with differing articulatory configuration which can be classified by measuring acoustic phonetic parameters such as band energy ratio, band energy differences, formants and formant differences. These acoustic phonetic parameters were tested in a classification experiment among labial nasal, alveolar nasal and velar nasal. An overall classification rate of 57.5% is obtained using the proposed acoustic phonetic parameters on the TIMIT database.

• The Journal of the Acoustical Society of Korea
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• v.32 no.2
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• pp.167-173
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• 2013

This work examines classification of diphthongs, as part of a distinctive feature-based speech recognition system. Acoustic measurements related to the vocal tract and the voice source are examined, and analysis of variance (ANOVA) results show that vowel duration, energy trajectory, and formant variation are significant. A balanced error rate of 17.8% is obtained for 2-way diphthong classification on the TIMIT database, and error rates of 32.9%, 29.9%, and 20.2% are obtained for /aw/, /ay/, and /oy/, for 4-way classification, respectively. Adding the acoustic features to widely used Mel-frequency cepstral coefficients also improves classification.

• Journal of Magnetics
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• v.4 no.1
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• pp.26-32
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• 1999

The HDDR process can be used as an effective means of processing of the coercive Nd-Fe-B-type or the Sm2Fe17Nx materials. The HDDR (hydrogenation, disproportionation, desorption, recombination) processed materials are feartured with a very fine microstructure. The thermomagnetic characteristics of the Nd-Fe-B-type or the Sm2Fe17Nx materials with fine microstructure due to the HDDR process were investigated. It has been found that the fine-microstructured hard magnetic materials showed an unusual TMA (Thermomagnetic analysis) tracting featured with a low and constant magnetization at lower temperature range and a peak just below their Curie temperatures when a low external field is applied. This thermomagnetic characteristic was immediate particularly in the TMA with a low applied field. This thermomagnetic characteristic was interpreted in terms of the competition between two counteracting effects; the decrease in magnetication due to the thermal agitation at an elevated temperature and the increase in magnetization resulting from the rotation of magnetization of the fine grains comparable to a critical single domain size due to the decreased magnetocrystalline anisotropy at an elevated temperature.

• Korean Journal of Plant Resources
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• v.20 no.4
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• pp.348-352
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• 2007

To investigate the effects of soil pH on plants, the seedlings of french marigold (Tagetes patula L.) was transplanted into the soils acidified with $H_{2}SO_{4}$ solutions (pH 5.3, 4.5, 3.9, 3.5). The level of malondialdehyde was significantly increased by soil acidification. As the pH levels decreased from 5.3 to 3.5, the contents of dehydroascorbate and oxidized glutathione of the plant were significantly increased. The antioxidative enzyme activities of the plant affected by soil acidification were increased as the pH decreased.