• Title/Summary/Keyword: Characteristics of difference

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A Study of Artificial Reef Subsidence in Unsteady Flow-Wave Field (비정상 흐름-파랑 공존장의 인공어초 침하특성에 관한 연구)

  • Yun, Sang Jun;Kim, Heon Tae
    • Journal of Ocean Engineering and Technology
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    • v.15 no.3
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    • pp.28-34
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    • 2001
  • The experimental studies for the artificial reef (AFR) subsidence characteristics in the unsteady flow field and in the unsteady flow-wave field were carried out. The difference of scou $r_sidence characteristics between in the steady flow field and in the unsteady flow field wad discussed and also the long-term subsidence characteristics in the unsteady flow field were investigated. AFR subsidence characteristics was discussed with Keulegan - Carpenter number(KC), Reynolds number (Re),. Shields number (Sn) and dimensionless time (t/Tt). And the difference of subsidence characteristics between in the unsteady flow and in the unsteady flow-wave field was discussed.ed.

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A Study of Artificial Reef Subsidence in Unsteady Flow-Wave Field (비정상 흐름-파랑 공존장의 인공어초 침하특성에 관한 연구)

  • Yun, Sang Jun;Kim, Heon Tae
    • Journal of Ocean Engineering and Technology
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    • v.15 no.3
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    • pp.29-29
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    • 2001
  • The experimental studies for the artificial reef (AFR) subsidence characteristics in the unsteady flow field and in the unsteady flow-wave field were carried out. The difference of scour/subsidence characteristics between in the steady flow field and in the unsteady flow field wad discussed and also the long-term subsidence characteristics in the unsteady flow field were investigated. AFR subsidence characteristics was discussed with Keulegan - Carpenter number(KC), Reynolds number (Re),. Shields number (Sn) and dimensionless time (t/Tt). And the difference of subsidence characteristics between in the unsteady flow and in the unsteady flow-wave field was discussed.

Ecological Characteristics of Lycoris radiata with Habitat Types

  • Lee, Jeom-Sook;Ihm, Byung-Sun;Kim, Ha-Song
    • The Korean Journal of Ecology
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    • v.26 no.5
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    • pp.247-250
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    • 2003
  • The investigation of ecological characteristics of Lycoris radiata was carried out in flooding (site I), half flooding (site II) and dry stands (site III). Seasonal change of air temperature showed similar patterns and that of light intensity showed quite difference among three L. radiata stands. Seasonal change of soil water content showed a great difference among three L. radiata stands. The study area was dominated by Pinus densiflora, P. thunbergii and L. radiata communities. The number of bulb in 1. radiata increased in September with bulb formation and decreased in January. Bulb weight in L. radiata was different from each site. The numbers of blossom were 23, 13 and 9, respectively in site I, II and III. The length of wreath were 17.0, 13.0 and 11.0cm, respectively, the length of stamen were 7.0, 6.4 and 6.5 cm, respectively and the length of stalk were 60.0, 45.0 and 42.0 cm, respectively in site I, II and III. The leaf of L. radiata developed rapidly in site I with sufficient water supply and lower light intensity, the number and the length of rootlets increased considerably in site III with insufficient water supply and higher light intensity, and the ecological characteristics in site II was intermediate between site I and site III. There was no great difference between the numbers of rootlets in site I and site II, which were due to sufficient water supply in two stands.

Comparison of Characteristics on the Flux-Lock and the Transformer Type SFCLs with Three Superconducting Units (3개의 초전도 소자를 갖는 자속구속형 SFCL과 변압기형 SFCL의 특성 비교)

  • Lee, Ju-Hyoung;Choi, Hyo-Sang
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.58 no.1
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    • pp.79-84
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    • 2009
  • In order to increase the capacity of the superconducting fault current limiter(SFCL), the current and voltage grades of the SFCL must be increased. As a method for the increase of the current and voltage grades of the SFCL, we compared the various characteristics between the flux-lock type SFCL "With three superconducting units connected in series and the transformer type SFCL using the transformer with three secondary circuits. One of three superconducting units had not quenched in the flux-lock type SFCL. Therefore, the unbalanced power burden happened because of the voltage difference generated by unbalanced quenching between the superconducting units. In the meantime, the three superconducting units were all quenched in the transformer type SFCL using the transformer, and the voltage difference generated between the superconducting units was decreased. Therefore, the difference of critical characteristics was complemented by distribution of fault current in accordance with the turn's ratio between primary and secondary windings. The unbalanced power burden of the superconducting units was reduced due to flux-share between the superconducting units in the transformer. In conclusion, the capacity increment of the SFCL using a transformer was easier due to equal distribution of voltages generated by simultaneous quench of the superconducting units. We think that the characteristics is improved more because of the decrease of saturation in the iron core if the secondary winding is increased in the SFCL using the transformer.

An Analysis of Energy Consumption Types Considering Life Patterns of Single-person Households (1인 가구 거주자의 생활패턴이 고려된 에너지소요량 유형 분석)

  • Lee, Seunghui;Jung, Sungwon;Lim, Ki-Taek
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.35 no.1
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    • pp.37-46
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    • 2019
  • The energy of the building is influenced by the user 's activity due to the population, society, and economic characteristics of the building user. In order to obtain accurate energy information, the difference in the amount of energy consumption by the activities and characteristics of building users should be identified. The purpose of the study is to identify the difference in the amount of energy consumption by the user's activities in the same building, and to analyse the relationship between user's activities and demographic, social and economic characteristics. For research, energy simulation is performed based on actual user activity schedule. The results of the simulation were clustered by using K-Means clustering, a machine learning technique. As a result, four types of users were derived based on the amount of energy consumption. The more energy used in a cluster, the lower the user's income level and older. The longer a user's indoor activity times, the higher the energy use, and these activities relate to the user's characteristics. There is more than twice the difference between the group that uses the least energy consumption and the group that uses the most energy consumption.

A Study on Quality Characteristics of Makpyeon made of Dry Milled Rice Powder according to Soaking Time (침지시간을 달리한 건식 쌀가루 막편의 품질특성)

  • Jo, Yun Ju;Yoon, Hye Hyun
    • Culinary science and hospitality research
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    • v.24 no.3
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    • pp.35-46
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    • 2018
  • This study investigated the quality characteristics of makpyeon made of dry milled rice powder according to soaking time. Makpyeon samples made of dry milled rice powder were analyzied with various soacking time, the moisture content, pH, Hunter's color value texture characteristics, attribute difference test and acceptance test. The moisture content of makpyeon did not indicate difference among samples. pH resulted in MS90 showed the lowest moisture content. The L-value (lightness) and a-value (greenness) result in that MS0 showed the highest and decreased according to soaking time. The b-value (yellowness) increased according to soaking time, MS90 showed the highest. TPA resulted in that MS90 indicated the highest hardness, chewiness, gumminess and the lowest adhesiveness. Hardness of makpyeon samples was higher than sulgitteok samples, adhesiveness was lower than those of sulgitteok in each soaking time. Based on attribute difference test, the score of brightness, moistness, glossy, particle size were decreased and firmness were increased according to soaking times. Flavor, taste and mouth feel attribute was stronger in makpyeon samples with the longer soaking time. Acceptance results showed that MS0 and MS30 (soaking for 30 min) were preferred the most. Also limitations and future research directions of this study were discussed.

A Study of the Seafood Dining Consumer Behavior by Demographic Characteristics (인구 통계적 특성에 따른 수산물 외식 소비행태에 관한 연구)

  • Kang, Hyo-Seul;Kim, Ji-Ung;Jang, Young-Soo
    • The Journal of Fisheries Business Administration
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    • v.50 no.1
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    • pp.39-54
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    • 2019
  • The purpose of this paper is to analyze the difference of seafood dining consumer behavior by demographic characteristics (age, gender). This research surveyed 251 people in Busan, Korea. t-test, one-way ANOVA, and MDS were used to identify the difference of consumer behavior by demographics. The result of the research revealed the difference between demographic characteristics and seafood dining consumption. 20's showed to accept the trendy dining culture represented by salmon, sushi and shrimp, and 30's also have similar tendency. 40's have higher spending tendency to seafood dining like tuna restaurants. 50's and 60's showed conservative consumption propensity represented by grilled fish, braised fish and raw fish restaurants. In gender analysis, male have higher frequency than female about grilled eel. In the future, the seafood dining market would be reorganized with the expansion of sushi, salmon and shrimp dishes, which can be classified as a new dining market. In this research, we suggested fisheries supply and production strategies according to age and gender.

A Study on Job Characteristics, Job Motivation and Job Performance of Public Health Nurses (보건소 간호사의 직무특성, 직무동기, 업무수행 비교)

  • June, Kyung-Ja;Kim, Hee-Gerl
    • Research in Community and Public Health Nursing
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    • v.8 no.2
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    • pp.250-261
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    • 1997
  • In Korea, visiting nursing services in pubic health centers have been in place since 1991. The purpose of this study is to compare the job characteristics, job motivation and job performance between visiting nurses and other public health nurses. 196 subjects were sent mailed questionnaires from Aug. to Sep., 1997. The response rate was 65.3%. Data were analyzed by a SPSSWIN program with a t-test, $X^2-test$, ANCOVA. The results were as follows : 1. The level of job ability in visiting nurses was higher than that of other public health nurses, but it was an insignificant difference(t=1.5975, p=.2078). Among job characteristics, skill variety was significantly higher in other public health nurses(t=8.2121, p=.0046); autonomy and feedback were significantly higher in visiting nurses(t=8.1877, p=.0047/t=7.7026, p=.0085). 2. There was no significant difference in the level of job motivation(t=.6485, p=.4216) and in job performance between the two groups (t=2.7393, p=.0995). In job performance, general nursing and organizational jobs were significantly higher in other public health nurses (t=4.8486, p=.1288/t=9.4237, p=.0024). 3. It was reconfirmed that there was, a significant difference in the level of skill variety, autonomy and feedback in analyzing age and career as covariates. 4. Significant positive relationship was found in job characteristics and job motivation(r=.5488, p=.0000). No significant relationship was found in job characteristics and job performance(r=.0486, p=.498). Through these results, it was supported that there were differences in some of the job characteristics and job performance between visiting nurses and other public health nurses. Therefore, it is requested to redesign job standards, training programs and management styles focusing on the job characteristics of visiting nurses.

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Spectral Characteristics and Formant Bandwidths of English Vowels by American Males with Different Speaking Styles (발화방식에 따른 미국인 남성 영어모음의 스펙트럼 특성과 포먼트 대역)

  • Yang, Byunggon
    • Phonetics and Speech Sciences
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    • v.6 no.4
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    • pp.91-99
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    • 2014
  • Speaking styles tend to have an influence on spectral characteristics of produced speech. There are not many studies on the spectral characteristics of speech because of complicated processing of too much spectral data. The purpose of this study was to examine spectral characteristics and formant bandwidths of English vowels produced by nine American males with different speaking styles: clear or conversational styles; high- or low-pitched voices. Praat was used to collect pitch-corrected long-term averaged spectra and bandwidths of the first two formants of eleven vowels in the speaking styles. Results showed that the spectral characteristics of the vowels varied systematically according to the speaking styles. The clear speech showed higher spectral energy of the vowels than that of the conversational speech while the high-pitched voice did the same over the low-pitched voice. In addition, front and back vowel groups showed different spectral characteristics. Secondly, there was no statistically significant difference between B1 and B2 in the speaking styles. B1 was generally lower than B2 when reflecting the source spectrum and radiation effect. However, there was a statistically significant difference in B2 between the front and back vowel groups. The author concluded that spectral characteristics reflect speaking styles systematically while bandwidths measured at a few formant frequency points do not reveal style differences properly. Further studies would be desirable to examine how people would evaluate different sets of synthetic vowels with spectral characteristics or with bandwidths modified.

Genetic Analysis of Major Characteristics in Flue-cured Tobacco (황색종 담배의 주요형질에 대한 유전분석)

  • 신승구;홍병희
    • Journal of the Korean Society of Tobacco Science
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    • v.13 no.2
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    • pp.59-65
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    • 1991
  • There was no a difference of genetic analysis among methods(means, joint scaling test, 3 Parameter model) . The magnitude of additive effects generally paralleled the magnitude of difference between parental means and appeared to be more independent from non-allelic interaction than did dominance effects, whereas the magnitude of dominance effects were inflated by non-allelic interaction. Additive effects were significant for all characteristics observed and it was a major effects in inheritance of number of leaves. Dominance effects were higher than additive effects for plant height, days to flower, flesh leaf weight per plant, curing rate, total alkaloid and total nitrogen.

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