• Title/Summary/Keyword: 속도양상

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Development of a Simultaneous Seed Separation and Drying Method of Red Pepper -Part I. Red Pepper Seed Separation Methods and Their Momentum Analysis- (고추의 동시탈종(同時脫種) 건조방법(乾燥方法)의 개발(開發)에 관한 연구(硏究) -제1보 고추씨의 분리방법(分離方法)과 운동량(運動量)의 분석(分析)-)

  • Chun, Jae-Kun;Park, Sang-Ki
    • Korean Journal of Food Science and Technology
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    • v.9 no.1
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    • pp.61-67
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    • 1977
  • Seed separation from half-cut red pepper were investigated with free falling, up-and-down shaking and rotating collision methods. The separation rates were related with impact appiied and the rotating case was distinguished from the other two methods. Beside the impact effect, velocity of the pod and tumbling factors were involved. Momentum effectiveness of seed separation were calculated as $2.50{\times}10^{-6}$, $2.09{\times}10^{-6}$, and $3.94{\times}10^{-8}$ for free falling, shaking and rotating method on the same velocity basis, respectively. The tendency of separation rate was similar to that of red pepper drying rate against time.

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The Analysis of Mapping Errors Induced in Learning the Concept of Reaction Rate with Analogies, and the Comparison of Mapping Errors by Analogy Presentation Types (비유를 사용한 반응 속도 개념 학습에서 유발되는 대응 오류에 대한 분석과 비유 표현 방식에 따른 비교)

  • Kim, Kyung-Sun;Byun, Ji-Sun;Lee, Seon-Woo;Kang, Hun-Sik;Noh, Tae-Hee
    • Journal of The Korean Association For Science Education
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    • v.28 no.4
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    • pp.340-349
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    • 2008
  • This study investigated the mapping errors induced in learning the concept of reaction rate with analogies, and compared these mapping errors by the analogy presentation types. Tenth graders (N=418) at a high school were assigned to the four groups by the target concepts and the analogy presentation types. The target concepts were 'concentration and reaction rate' and 'temperature and reaction rate'. In presenting analogy, the verbal and the verbal/pictorial analogs were used. After the students learned one of the analogs, a mapping test was administered. From the analysis, eight types of mapping errors were identified: overmapping, artificial mapping, failure to map, rash mapping, mismapping, mapping of a superficial feature, retention of a base feature, and impossible mapping. According to the analogy presentation types and the features of the target concepts, there were some differences in the frequencies of mapping errors. Educational implications of these findings are discussed.

Image analytical observation on the growth and development of Clonorchis sinensis in rats (흰쥐 감염 간흡충의 성장 및 발육에 대한 형태계측학적 관찰)

  • Jin KIM
    • Parasites, Hosts and Diseases
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    • v.33 no.4
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    • pp.281-288
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    • 1995
  • For the two-dimensional observation on the growth and development of CLonorchis sinensis, an image analysis system (IBAS 2000, Kontron, Germany) was used in this study. On 3, 6, 9, 12, 15, 21, 30 and 90 days of infection, 474 worms were collected from rats infected with 50 metacercariae each. The overall recovery rate was 31.6%. The worms grew rapidly in their length and width up to 30 days of infection and then, did slowly to 90 days of infection. However, the growth pattern of body area was not similar to that of body length and width, because the body area increased continuously even after 30 days of infection. With the image analysis system, the sizes of irregular-shaped genital organs were measured easily, which showed sigmoidal growth patterns . The growth rate of genital organs increased rapidly. until 21 days of infection when the uterus was filled with numerous eggs, and then gradually slowed down to 90 days. There was no difference in growth pattern between the anterior and posterior testis. The seminal receptacle , however, showed an abrupt increase in size between 15 to 21 days of infection when it was filled with condensed semen. Therefore, the growth pattern of seminal receptacle might be used as another criteria to estimate the extent of sexual maturation of C. sinensis. From this study, it is suggested that image analysis system is very useful to reveal the growth and development pattern of C. sinensis, especially of their internal organs.

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Studies on the Ethanol Production by Clostridium thermosaccharolyticum (Clostridium thermosaccharolyticum에 의한 에탄올생산에 관한 연구)

  • 조은경;이윤광;변유량;유주현
    • Microbiology and Biotechnology Letters
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    • v.13 no.4
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    • pp.397-402
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    • 1985
  • The fermentation of various sugars by C. thermosaccharolyticum was examined under pH controlled, anaerobic condition. The kinetic model for Product formation at various sugars was the combination of growth and non-growth associated mode. In the utilization of a single sugar, glucose was the best carbon source for growth. The specific growth rate of glucose, xylose and cellobiose were 0.363 h$^{-1}$, 0.242 h$^{-1}$ and 0.144 h$^{-1}$ respectively. The production of ethanol from glucose showed a negatively growth associated mode, so the higher growth rate decreased the productivity of ethanol. The maximum concentrations of the produced ethanol were 2.42 g/l, 3.76 g/l, and 3.4 g/l on glucose, xylose, and cellobiose. No glucose was detected during cellobiose fermentation. Sequential utilization of sugars was observed in the mixtures of glucose, xylose and cellobiose. It preferred glucose, followed by xylose and then cellobiose. The presence of other sugars had little or no effect on the rate of another sugar utilization. Cell lysis at the end of fermentation occured more slowly in the mixtures of sugars than a single sugar.

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Comparative Analysis of the Sediment Transport Region based on the Lagrangian Concept (Lagrangian 개념에 의한 부유토사 확산범위 비교분석)

  • Cho, Hong-Yeon;Kim, Chang-Il;Lee, Khil-Ha
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.19 no.2
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    • pp.105-112
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    • 2007
  • Sediment transport model based on the Lagrangian concept considering the grain size distribution(GSD) was setup and the change of the sediment diffusion range was analysed in the condition of considering and not considering the GSD. The GSD curve is assumed as the Log-normal distribution function in order to consider the GSD with respect to the Lagrangian concept and the random numbers, i.e. sediment particles, are generated based on the distribution function. The sediment particles is assumed as the spherical type and the random numbers based on the sediment weight is converted to the sediment diameters. Sediment transport patterns are analysed by the settling simulation, in which the settling velocity is computed by the van Rijn formulae and the horizontal diffusion coefficient is used as the constant parameter. The diffusion patterns are very similar to the patterns with GSD condition. The diffusion range defined as the range including 90%, 99% sediment weight of the total sediment weight, however, is larger than without considering GSD condition in 90%-option and shorter than with considering GSD condition in 99-option, respectively. The diffusion range is defined as tile p-percentage of the cumulative sediment weight region with reference to the 50% region, 90%- option, 99%-option, respectively.

Residues of Benomyl and Bitertanol in Apples Treated as Postharvest Fungicides under Different Storage Conditions (수확후 처리제로서 Benomyl과 Bitertanol이 처리된 사과의 저장조건에 따른 잔류량)

  • Lee, Eun-Joo;Kim, Jang-Eok
    • Korean Journal of Environmental Agriculture
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    • v.15 no.4
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    • pp.434-441
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    • 1996
  • This study was conducted to clarify the degradation pattern, safety evaluation and penetration ratio of benomyl and bitertanol to apple used as postharvest fungicides during CA(controlled atmosphere) and cold storage. In CA storage, the degradation of benomyl and bitertanol in stored apple was slow at the early stage, while that in cold storage was, on the contrary, faster at the early stage. The initial concentrations of benomyl and bitertanol in apples applied at the standard application concentrations were 2.24 and 1.54mg/kg, respectively, and their residual amounts were below the maximum residue limits, 1mg/kg at 135 and 96 days in CA storage, 115 and 70 days in cold storage, respectively. The half-lives of benomyl and bitertanol in stored apples were 124 and 130 days in CA storage, 101 and 111 days in the cold storage, respectively, indicating that the degradation was faster in cold storage than in CA storage. The residual amount of benomyl and bitertanol in stored apples was retained more in peels than in pulps of apples.

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Textural Characteristics and Transport Mode of Surface Sediments of a Tidal Sand Ridge in Gyeonggi Bay, Korea (경기만 조류성 사퇴 표층 퇴적물의 입도 특성 및 이동 양상)

  • CHOI, JIN-HYUK;PARK, YONG AHN
    • 한국해양학회지
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    • v.27 no.2
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    • pp.145-153
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    • 1992
  • From the analyses of 16 bottom sediment samples and current data obtained during field expert ments from August to September 1987, the textural characteristics and transport mode of sand grains of a tidal sand ridge in Gyeonggi Bay are studied. The textural characteristic of the bottom sediments are diverse depending on their location on the tidal sand ridge. Sands on the crest are well sorted. near symmetric in skewness. leptokurtic in kurtosis. and are unimodal in peakedness. On the other hand, Poorly sorted gravelly sands in the trough are coarse skewed in skewness and plartkurtic in kurtosis. The mean values of U/SUB 100/ (velocity at one meter above bottom) and U/SUP */ (boundary shear velocity) are calculated to be 41.4 cm/sec and 2.39 cm/sec, respectively. From the analyses of characteristics of the sediments and currents in the study area, it can be concluded that almost all the sands of the tidal sand ridge (esp. on the crest) are transported as bedload (mainly as saltation).

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Sedimentation Characteristics of Dredged Soil by Geo-Centrifuge (원심모형실험을 통한 준설토의 퇴적 특성)

  • Ahn, Kwangkuk;Lee, Kyuhwan;Heo, Yol;Kang, Hongsig
    • Journal of the Korean GEO-environmental Society
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    • v.15 no.3
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    • pp.49-55
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    • 2014
  • Characteristics of sedimentation of dredged soil is depended on the field condition and characteristics of dredged soil because dredged fill ground was formed by various field condition, sedimentation and self-weight consolidation process of dredged soil. Dredged fill ground is formed as separated sedimentary layer by characteristics of dredged soil. Therefore, it requires some special test method to consider a various field condition, characteristics of sedimentation and self-weight consolidation of dredged soil. In this study, in order to identify the characteristics of sedimentation of dredged soil with disposing velocity geo-centrifuge test and laser particle size analyzer were performed. As a results, river and mixed dredged soil show the separation sedimentation by soil particle size. And sedimentation of clayey dredged soil is parallel to the bottom surface of dredged fill space.

A Study on the Future Development of Korean Institutional Repository through an Analysis of Developmental Aspects of Japanese (일본의 전개 양상을 통해서 본 한국 기관 레포지토리의 과제)

  • Cho, Jane
    • Journal of the Korean Society for information Management
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    • v.26 no.1
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    • pp.35-55
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    • 2009
  • IR(Institutional Repository) is an indispensable instrument for not only long time preservation of intellectual products but also for shifting commercial publishing company-dominated academic communication stream. In Korea, dCollection project of Ministry of education, science and technology has contributed on immediate, integrated circulation of distributed research products. dCollection is already one of the few integrating instrument for distributed academic resources, but it has not been university's voluntary instrument to announce their research accomplishments and to realize open access. On the other hand, Japanese government has promoted universities' IR operation through "Next generation infrastructure construction project." Even though distributing speed is relatively low, each university made ripe operating skill by their selves and realize its own purpose. This study comparatively analyzed policy and current status of Institutional Repository in Korea and Japan from various viewpoints. And also it proposed directions of development about Korean Institutional Repositories.

Endocrine Function and Growth in Children with Craniopharyngioma (소아 두개인두종 환자에서 치료 전후의 뇌하수체 기능과 성장 및 체중 변화)

  • Chung, Yoo Mi;Shin, Choong Ho;Yang, Sei Won
    • Clinical and Experimental Pediatrics
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    • v.46 no.3
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    • pp.277-283
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    • 2003
  • Purpose : Craniopharyngiomas are often accompanied by severe endocrine disorders. Although there is universal growth hormone deficiency(GHD), the resulting growth pattern is very heterogeneous. We report the growth and endocrine outcome of 44 children with craniopharyngioma, with emphasis on initial symptoms, growth before and during growth hormone(GH) treatment and spontaneous growth in spite of GHD. Methods : We performed a retrospective study of 44 children treated at our centre between 1984 and 2002. Results : About 30% of patients had symptoms suggesting endocrine disorder at diagnosis. After surgery, multiple endocrinopathies were almost universal. Before GH therapy, height velocity was $8.00{\pm}2.71cm/yr$ in the normal growth group(n=11) and $1.79{\pm}1.10cm/yr$ in the subnormal growth group(n=7) during the first year and during the second year, $6.76{\pm}2.49cm/yr$ and $2.29{\pm}1.33cm/yr$, respectively. There was no difference of body mass index(BMI) change between before and after surgery in the two groups. Height standard deviation score(SDS) was $-1.46{\pm}0.74$ in the normal growth group and $-0.43{\pm}0.97$ in the subnormal growth group. Before GH treatment height SDS was $-1.31{\pm}1.25$ and BMI was $20.46{\pm}3.60$. During GH treatment, height SDS increased to $-0.60{\pm}1.37$ in the first, and to $-0.41{\pm}1.54$ in the second year(P<0.05), but BMI did not change significantly. Conclusion : The endocrine morbidity could develop in most children with craniopharyngioma before and after the operation and should be managed properly. Although all treated patients benefit from GH therapy, further studies are necessary to find out the possible mechanism of growth regulation in normally growing children, despite GH deficient.