• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.505-506
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• 2004

이어폰과 헤드폰의 성능 향상을 위해서는 특성에 대한 정확한 측정과 평가가 요구된다. 이어폰과 헤드폰은 room 과 같은 acoustic channel 을 거치지 않고 청취자의 귀에 직접 소리가 전달되며 ear canal 특성이 포함되기 때문에 스피커와는 다른 기준이 필요하다. 그러나 사람 귀의 canal 특성은 개인에 따른 편차가 심하여 정확한 측정 및 성능 평가에 어려움이 따른다. 본 논문에서는 이어폰과 헤드폰의 특성을 측정하는 적절한 방법을 고찰하고 측정된 데이터를 이용하여 음질 성능을 평가할 수 있는 객관적인 방법을 제시하고자 한다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.183-188
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• 2003

This study is to make the fundamentals of sound quality evaluation in regard of acoustical characteristics of passenger compartment. The deviation of frequency response function level within audible frequency is evaluated at receiving point in the research of room acoustics. In this study, frequency response function is the one between speaker and driver's ear positions. The positions of driver and audio speakers are optimized by analysis of acoustic mode of acoustic cavity. The main reflection planes are determined by analysis sound ray path diffused at optimized speaker positions. Finally, designer selects acoustical material by analysis of absorption effect of acoustical materials on the main reflection planes in order to avoid to distortion and fluctuation of frequency response function..

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.22 no.1
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• pp.141-147
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• 2009

Objective : We investigated the effects of BOM Gunbisoyeom-tang(Jianbixiaoyan-tang) Gamibang having prescribed clinically to patients with perennial allergic rhinitis. Methods : We prescribed BOM Gunbisoyeom-tang(Jianbixiaoyan-tang) Gamibang for 1 month to 77 patients visiting to KimKiJoon Orentalclinic BOM from January 1 to December 31, 2008 with perennial allergic rhinitis and analysised the questionnaire(symptom severity assessment) before and after treatment. Results : BOM Gunbisoyeom-tang(Jianbixiaoyan-tang) Gamibang improved significantly all nosal symptoms(sneezing, runny nose, congestion, itchy nose and postnasal drip), some non-nasal symptoms(eye and throat symptoms, headache and mental function) except chromic cough and ear symptoms and quality of life. Conclusion : BOM Gunbisoyeom-tang(Jianbixiaoyan-tang) Gamibang cured effectively patients with perennial allergic rhinitis by 1 month treatment but not perfectly. So further studies are needed for treatment duration and changes of pathological index before and after treatment.

• Radiation Oncology Journal
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• v.38 no.2
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• pp.84-92
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• 2020

Patients undergoing radiation therapy for head and neck cancer (HNC) experience significant early and long-term side effects. The likelihood and severity of complications depends on a number of factors, including the total dose of radiation delivered, over what time it was delivered and what parts of the head and neck received radiation. Late side effects include: permanent loss of saliva; osteoradionecrosis; radiation recall myositis, pharyngoesophageal stenosis; dental caries; oral cavity necrosis; fibrosis; impaired wound healing; skin changes and skin cancer; lymphedema; hypothyroidism, hyperparathyroidism, lightheadedness, dizziness and headaches; secondary cancer; and eye, ear, neurological and neck structures damage. Patients who undergo radiotherapy for nasopharyngeal carcinoma tend to suffer from chronic sinusitis. These side effects present difficult challenges to the patients and their caregivers and require life-long strategies to alleviate their deleterious effect on basic life functions and on the quality of life. This review presents these side effects and their management.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.3
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• pp.211-220
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• 1999

The corn is mostly planted in mid-April in single-cropping silage system if possible, however, in a double-cropping silage system, the corn planting date is delayed until after the mid-May. The objective of this study was to evaluate agronomic characteristics and forage performance of the eight government recommended corn hybrids for silage at two dates of planting. Split-plot design replicated three times was used, that is, main plots were planting dates, sub-plots were eight hybrids at Suweon in 1997. Days from planting to silking of optimum planting was 84 days and that of late was 69 days. The difference in silking day among the hybrids was 6 days at optimum planting and 2 days at late planting. Plant height of optimum planting corn was higher than that of late one, however, ear height and stem diameter of optimum planting were lower than those of late planting corn. Among the corn hybrids tested, plant heights of 'P3156' and 'P3163' were higher than those of the other hybrids. Ear height of 'DK713' was the lowest among the corn hybrids and stem diameter of 'P3394' was thicker than that of the other hybrids. European corn borer(ECB) damage(16.6%) at optimum planting was lower than that(49.9%) of late, however, there were no significant ECB damage differences among the corn hybrids tested. Whole plant dry matter(DM) contents of 'P3525', 'P3394' and 'P3352' hybrids were higher than those of the other corn hybrids at harvest. Ear percentages of the total dry matter(DM) of 'P3394' and 'P3156' were higher than those of the other corn hybrids. Dry matter(DM) and total digestible nutrients(TDN) yields(19,696 and 14,621kg/ha) at optimum planting were higher than those (17,163 and 12,570kg/ha) of late planting, while there were no significant differences in DM and TDN yields among the corn hybrids tested. And those hybrids with greater proportion of grain in the whole plant have higher DM and TDN yields. Correlation coefficients for days from planting to silking with DM and TDN yields were $0.84^{**}$ and $0.87^{**}$, and those for ear percent were $0.86^{**}$ and $0.87^{**}$. Results of this study indicate that optimum planting date(15 April) is better than late planting date(16 May) in agronomic characteristics and forage production of silage corn. Days from planting to silking and ear percent as welI as other characters are important factors screening the corn hybrid for silage.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.3
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• pp.340-344
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• 2005

In high-income Asian countries like Korea and Japan, per capita rice consumption has declined because of the change in consumer' favorite foods from rice to high-cost quality foods. This has forced farmers to reduce rice production. Although fodder rice could be another option to be cultured by farmers, available information concerning rice grain silage has been limited. In the present study, therefore, the difference in the quality of fodder rice silage prepared from either whole crop or grain at different ripening stages was compared. Various supplements were also added into whole crop and grain silages of fodder rice before ensiling, and thereafter, the palatability of prepared silages was determined by beef cattle. At ear emergence stage, the pH values for both grain and whole crop silages were approximately 4.5. In both grain and whole crop silages, the pH values were significantly increased by progressing ripening stages from milk-ripe stage to yellow-ripe stages, and the increase in pH value for grain silage was faster than that for whole crop silage. In the grain silage, the higher lactic acid (LA) content in grain silage seemed to be, the lower pH value was. Both in grain and whole crop silages, pH was significantly decreased by supplementation with LA bacteria. There were no significant differences in feed intake among any treatment groups.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.8C
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• pp.822-829
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• 2009

This paper proposes a new method of improving the quality of High Efficiency Advanced Audio Coding (HE-AAC). HE-AAC encodes input source by allocating bits for each scalefactor bands appropriately according to human ear's psychoacoustic property. As a result, insufficient bits are assigned to the bands which have relatively low energy. This imbalance between different energy bands can cause decreasing of sound quality like musical noise. In the proposed system, a Linear Prediction (LP) module is combined with HE-AAC as a pre-processor to improve sound quality by even bits distribution. To apply accurate human being's psychoacoustic property, the psychoacoustic model uses Fast Fourier Transform (FFT) spectrum of original input signal to make masking threshold. In its implementation, masking threshold of psychoacoustic model is normalized using the LP spectral envelope in prior to quantization of the LP residual. Experimental result shows that, the proposed algorithm allocates bits appropriately for insufficient bits condition and improves the performance of HE-AAC.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.4
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• pp.249-257
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• 2022

This study was conducted to comparison analysis growth characteristics, yield and forage quality of 18silage corn varieties grown in paddy and upland fields. In this condition, days to silking of Sinhwangok was the shortest with 78 days and Kangdaok the longest with 92 days. Moreover it was confirmed that the difference of days to silking at this condition greatly occurred in the late species than in the precocious species. The height and ear height ratio of corn grown in paddy decreased by 5~10% and increase by 10~15% compared to upland, respectively. It was confirmed that the ear ratio of corn which enhances the forage quality was highest in Sinhwangok at paddy and upland and most of the varieties decreased by 10~30% at paddy rather than upland. The length of ear was also reduced by 10~25%. In fresh yield, Dacheongok showed the highest yield at 65,750 kg/ha in upland and 38,830 kg/ha in paddy. Similar to the fresh yield, dry and TDN yield in Dacheongok also showed the highest yield at 36,910 kg/ha, 18,040 kg/ha in upland and 21,670 kg/ha, 14,390 kg/ha in paddy, respectively. As a result of analyzing crude protein and starch from seeds to evaluate the feed value of corn for silage, there was no difference between cultivars grown in this condition. In addition, as a result of analyzing the contents of ADF and NDF using leaves, stems and seeds, the contents of leaves and stems were lower in P3394 and P1543 at the upland and lower in Singwangok and Daanok when cultivated at paddy. Moreover ADF and NDF contents were decreased in some varieties in paddy rather than upland. Therefore, there is no significant difference in the feed value of corn varieties grown in this condition, it is possible to cultivate corn in paddy if normal growth is achieved through drainage management.

• Journal of Animal Science and Technology
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• v.50 no.1
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• pp.1-8
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• 2008

This study was conducted to develop a traceability system for systematic animal identifi- cation to increase efficiency of animal production, post production and processing to ensure that quality and sanitary meat products reach the consumers of the entire country. The new animal identification traceability system was designed for easy management, data collection and storage considering bar code, registration number and farm number.Specifically the system aimed 1) To provide standard radio frequency technology identification (RF-ID) for livestock management, standard of ear tag, microchip and ear tag identification equipment, 2) To guarantee meat product label thereby safeguarding the consumers 3) To give incentives to farmers for producing quality meat products and 4) To provide unified system for national livestock management.Results of the research which started in July 2003 which was used by several farmers’ cooperatives and Department Store revealed the feasibility of using the RF-ID system although much will be done to conform to global nomenclatures.

• Journal of Music and Human Behavior
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• v.21 no.2
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• pp.107-134
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• 2024

This study aims to classify the semantic words commonly used to evaluate sound quality and to analyze their differences in reflecting the level of musical stimuli. Participants were thirty-one music majors in their 20s and 30s, with an average of 9.4 years of professional training. Each participant listened to nine pieces of music with variations in texture and instrument type and evaluated them using 18 pairs of semantic words describing sound quality. A factor analysis was conducted to group words influenced by the same latent factor, and a multivariate ANOVA determined the differences in ratings based on texture and instrument type. Radar charts were also drawn based on the identified sets of semantic words. The results showed that four factors were identified, and the word pairs 'soft-hard,' 'dull-sharp,' 'muddy-clean' and 'low-high' showed significant differences based on the level of musical stimuli. The radar charts effectively distinguished the sound quality evaluations for each music. These results indicate that developing Korean semantic words for sound quality evaluation requires a structure different from the previous categories used in Western countries and that linguistic and cultural factors are crucial. This study will provide foundational data for developing a verbal sound quality evaluation framework suited to the Korean context, while reflecting acoustic attributes in music listening.