• Title/Summary/Keyword: Quantitative research

Search Result 7,135, Processing Time 0.039 seconds

Dynamics of Barrel-Shaped Young Supernova Remnants (항아리 형태 젊은 초신성 잔해의 동력학)

  • Choe, Seung-Urn;Jung, Hyun-Chul
    • Journal of the Korean earth science society
    • /
    • v.23 no.4
    • /
    • pp.357-368
    • /
    • 2002
  • In this study we have tried to explain the barrel-shaped morphology for young supernova remnants considering the dynamical effects of the ejecta. We consider the magnetic field amplification resulting from the Rayleigh-Taylor instability near the contact discontinuity. We can generate the synthetic radio image assuming the cosmic-ray pressure and calculate the azimuthal intensity ratio (A) to enable a quantitative comparison with observations. The postshock magnetic field are amplified by shearing, stretching, and compressing at the R-T finger boundary. The evolution of the instability strongly depends on the deceleration of the ejecta and the evolutionary stage of the remnant. the strength of the magnetic field increases in the initial phase and decreases after the reverse shock passes the constant density region of the ejecta. However, some memory of the earlier phases of amplification is retained in the interior even when the outer regions turn into a blast wave. The ratio of the averaged magnetic field strength at the equator to the one at the pole in the turbulent region can amount to 7.5 at the peak. The magnetic field amplification can make the large azimuthal intensity ratio (A=15). The magnitude of the amplification is sensitive to numerical resolution. This mens the magnetic field amplification can explain the barrel-shaped morphology of young supernova remnant without the dependence of the efficiency of the cosmic-ray acceleration on the magnetic field configuration. In order for this mechanism to be effective, the surrounding magnetic field must be well-ordered. The small number of barrel-shaped remnants may indicate that this condition rarely occurs.

Quality Characteristics of Sulgidduck Using Dry Rice Powder Added with Different Amounts of Milk (우유를 첨가한 건식 쌀가루 설기떡의 품질 특성)

  • Park, Young-Mi;Yoon, Hye-Hyun
    • Culinary science and hospitality research
    • /
    • v.18 no.5
    • /
    • pp.267-278
    • /
    • 2012
  • The purpose of this study was to investigate the quality characteristics of Sulgidduck made with commercial dry rice powder, providing an optimal milk ratio and soaking time for dry powder in water to make Sulgidduck using dry rice powder. The Sulgidduk samples with dry rice powder were prepared with two soaking times (0, 30 min) and different amounts of milk (0, 20, 40, 60%), and analyzed for moisture content, Hunter's color value, texture characteristics and sensory evaluation. The moisture content of the samples ranged from 36.37% to 39.80% and the highest moisture quantity was showed in the group with 20% of milk and 30min of soaking time(SM20). The L-value was the highest in the group with 20% of milk and 0min of soaking time(M20). The b-value was increased with the amount of milk and soaking time increased, showing the highest in the group with 60% of milk and 30min of soaking time(SM60). TPA showed that SM20 had the lowest hardness and the highest adhesiveness. Chewiness, gumminess and cohesiveness were the highest in the group with 60% of milk and 0min of soaking time(M60). Based on quantitative descriptive sensory evaluations, the score of white color and moistness was showed high in the group with 0% of milk and 0min of soaking time(M0), and white powder on the surface was shown the most in the group with 20% of milk and 30min of soaking time(SM20). The score of moistness, springiness and chewiness were highest in the group with 20% of milk and 0min of soaking time(M20). Sulgidduk made with 20% of milk and 0min of soaking time(M20) was the most preferable in color, flavor, taste, and overall acceptability.

  • PDF

Noncondensable gas's influence in waster vapor absorption accompanying interfacial disturbance into aqueous solution of LiBr

  • Dong-Ho RIE;Keun-Oh Lee
    • Journal of the Korean Society of Safety
    • /
    • v.7 no.2
    • /
    • pp.63-70
    • /
    • 1992
  • The aim of this research is to obtain a basic quantitative understanding of the effect of a noncondensable gas on the absorption of water vapor by a $H_2O$ / LiBr combination with n-octanol as the surfactant. Nonflowing aqueous solutions of LiBr (40,45,50 mass%) were exposed to saturated water vapor following the addition of an n-octanol sufactant (0.01 and 0.6 mass%). A small amount of a noncondensable gas (air) was allowed into the absorber (0.03 volume%) and its effect was analyzed by measuring the amount of water vapor absorbed. This study will aid to predict the performance of heat pump and safety operating condition when the noncondensable gas is not allowed in the absorber The results indicate that, in the presence of small amounts of a noncondensable gas, vapor absorption enhancement ratios are less than half o( those obtained under the same experimental conditions when a noncondensable gas is not present (1). The presence of a noncondensable gas causes the partial vapor pressure of air to increase at the vapor / liquid interface, which results in an instability of vapor absorption rate nd. hence, in an inhibition of interfacial disturbance.

  • PDF

Effect of Temperature and Various Pre-treatments on Germination of Hippophae rhamnoides Seeds (갈매보리수나무 종자의 온도 및 여러 가지 전처리에 따른 발아반응)

  • Choi, Chung-Ho
    • Korean Journal of Plant Resources
    • /
    • v.25 no.1
    • /
    • pp.132-141
    • /
    • 2012
  • This study was carried out to test seed germination responses to temperatures and pre-treatments in Hippophae rhamnoides, which has many abilities in antioxidant activity, soil improvement and erosion control. H. rhamnoides seeds were placed at 10, 15, 20, 25, 30 and $35^{\circ}C$ under light condition. As the results, germination percentage (GP) was the highest at 15 and $20^{\circ}C$, and mean germination time (MGT), germination rate (GR) and germination value (GV) were the highest at $25^{\circ}C$. Quadratic and linear regression model were used to determine the cardinal temperatures such as base ($T_b$), maximum ($T_m$) and optimum ($T_o$) temperature for germination. In quadratic regression model using PG, $T_b$, $T_m$ and $T_o$ was estimated as 0.6, 36.4 and $18.5^{\circ}C$, respectively, and temperature range for germination was $35.8^{\circ}C$. In linear regression model using GR, $T_b$, $T_m$ and $T_o$ was estimated as 8.3, 35.4 and $25.3^{\circ}C$, respectively, and temperature range for germination was $27.2^{\circ}C$. Germination properties were investigated after H. rhamnoides seeds were treated by prechilling (1, 2, 4, 6 and 8 weeks), stratification (2, 4, 6 and 8 weeks), solid matrix priming (seed : carrier : water = 5 : 1 : 7, 8, 9 and 10), osmo-priming (-0.25, -0.5, -1.0 and -1.5 MPa) and calcium chloride ($CaCl_2$) -priming (100, 200, 300 and 400 mM). The highest GP was observed in $CaCl_2$ 300 and 400 mM treatments, and MGT was the shortest in stratification 6 and 8 weeks treatments. GR and GV were the highest and GP was the second highest when seeds were prechilled for 1 and 2 weeks. Consequently, prechilling 1 or 2 weeks treatment was considered as the appropriate method when we contemplate qualitative and quantitative effects in seedling production.

The Recognition Characteristics of Science Gifted Students on the Earth System based on their Thinking Style (과학 영재 학생들의 사고양식에 따른 지구시스템에 대한 인지 특성)

  • Lee, Hyonyong;Kim, Seung-Hwan
    • Journal of Science Education
    • /
    • v.33 no.1
    • /
    • pp.12-30
    • /
    • 2009
  • The purpose of this study was to analyze recognition characteristics of science gifted students on the earth system based on their thinking style. The subjects were 24 science gifted students at the Science Institute for Gifted Students of a university located in metropolitan city in Korea. The students' thinking styles were firstly examined on the basis of the Sternberg's theory of mental self-government. And then, the students were divided into two groups: Type I group(legislative, judicial, global, liberal) and Type II group(executive, local, conservative) based on Sternberg's theory. Data was collected from three different type of questionnaires(A, B, C types), interview, word association method, drawing analyses, concept map, hidden dimension inventory, and in-depth interviews. The findings of analysis indicated that their thinking styles were characterized by 'Legislative', 'Executive', 'Anarchic', 'Global', 'External', 'Liberal' styles. Their preference were conducting new projects and using creative problem solving processes. The results of students' recognition characteristics on earth system were as follows: First, though the two groups' quantitative value on 'System Understanding' was very similar, there were considerable distinctions in details. Second, 'Understanding the Relationship in the System' was closely connected to thinking styles. Type I group was more advantageous with multiple, dynamic, and recursive approach. Third, in the relation to 'System Generalization' both of the groups had similar simple interpretational ability of the system, but Type I group was better on generalization when 'hidden dimension inventory' factor was added. On the system prediction factor, however, students' ability was weak regardless of the type. Consequently, more specific development strategies on various objects are needed for the development and application of the system learning program. Furthermore, it is expected that this study could be practically and effectively used on various fields related to system recognition.

  • PDF

Gait Analysis of a Pediatric-Patient with Femoral Nerve Injury : A Case Study (대퇴신경 손상 환아의 보행분석 : 사례연구)

  • Hwang, S.H.;Park, S.W.;Son, J.S.;Park, J.M.;Kwon, S.J.;Choi, I.S.;Kim, Y.H.
    • Journal of Biomedical Engineering Research
    • /
    • v.32 no.2
    • /
    • pp.165-176
    • /
    • 2011
  • The femoral nerve innervates the quadriceps muscles and its dermatome supplies anteromedial thigh and medial foot. Paralysis of the quadriceps muscles due to the injury of the femoral nerve results in disability of the knee joint extension and loss of sensory of the thigh. A child could walk independently even though he had injured his femoral nerve severely due to the penetrating wound in the medial thigh. We measured and analyzed his gait performance in order to find the mechanisms that enabled him to walk independently. The child was eleven-year-old boy and he could not extend his knee voluntarily at all during a month after the injury. His gait analysis was performed five times (GA1~GA5) for sixteen months. His temporal-spatial parameters were not significantly different after the GA2 or GA3 test, and significant asymmetry was not observed except the single support time in GA1 results. The Lower limb joint angles in affected side had large differences in GA1 compared with the normal normative patterns. There were little knee joint flexion and extension motion during the stance phase in GA1 The maximum ankle plantar/dorsi flexion angles and the maximum knee extension angles were different from the normal values in the sound side. Asymmetries of the joint angles were analyzed by using the peak values. Significant asymmetries were found in GA1with seven parameters (ankle: peak planter flexion angle in stance phase, range of motion; ROM, knee: peak flexion angles during both stance and swing phase, ROM, hip: peak extension angle, ROM) while only two parameters (maximum hip extension angle and ROM of hip joint) had significant differences in GA5. The mid-stance valleys were not observed in both right and left sides of vertical ground reaction force (GRF) in the GA1, GA2. The loading response peak was far larger than the terminal stance peak of vertical ground reaction curve in the affected side of the GA3, GA4, GA5. The measured joint moment curves of the GA1, GA2, GA3 had large deviations and all of kinetic results had differences with the normal patterns. EMG signals described an absence of the rectus femoris muscle activity in the GA1 and GA2 (affected side). The EMG signals were detected in the GA3 and GA4 but their patterns were not normal yet, then their normal patterns were detected in the GA5. Through these following gait analysis of a child who had selective injuries on the knee extensor muscles, we could verify the actual functions of the knee extensor muscles during gait, and we also could observe his recovery and asymmetry with quantitative data during his rehabilitation.

An Analytical Study on the Growth Factors of Bamboo Culm by the Multivariate Analysis (다변량분석(多變量分析)에 의(依)한 죽간(竹稈)의 성장해석(成長解析)에 관(關)하여)

  • Lee, Kwang Nam;Cha, Gyung Soo
    • Journal of Korean Society of Forest Science
    • /
    • v.76 no.4
    • /
    • pp.338-347
    • /
    • 1987
  • The research was carried out to investigate the related phenomena, the latent structures and synthetical characteristics in various growth factors of Phyllostachys bambusoides Sieb. et Zucc. growing at Damyang gun, Chollanamdo, using multivariate analysis. 1. By synthetical characteristics in canonical correlation between height-growth factor group and diameter-growth factor group, the former was determined by the culm height ($x_1$), and the latter by the. diameter of the largest internode($x_7$). And for those between quantitative growth factor group and qualitative growth factor group, the former was determined by the surface area($x_{10}$), and the latter by the diameter of the largest internode ($x_7$). 2. The ten growth factors of bamboo culm were simplified by two principal components on the basis of accumulated proportion aimed at 90%. The first principal component($Z_1$) as a "size factor" showed high correlation with growth factors except eye-height diameter($x_5$). The second principal component($Z_2$) as a "shape factor" showed high correlation only with $x_5$. 3. The bamboo culm, and the latent phenomenon between their growth factors could be determined by two common factors showing high communality(94.16%). The ten growth factors can be grouped into two attribute factors: quantity and quality. 4. The bamboo culms can be classified into five types: total, volume, shape-quality, inferior and middle.

  • PDF

Effect of Drench Application of Growth Retardants on Growth and Development in Cut Lilies (절화 백합의 생장과 발육에 미치는 생장억제제의 관주처리 효과)

  • Park, In Sook;Park, Song Kyoung;Naing, Aung Htay;Hwang, Yoon Jung;Kang, Si-Yong;Lim, Ki Byung
    • FLOWER RESEARCH JOURNAL
    • /
    • v.18 no.3
    • /
    • pp.165-170
    • /
    • 2010
  • This study was carried out to investigate the effect of three different growth retardants for applying pot or bedding plant with 'Rialto', 'Elodie', and 'Raizan'. Ancymidol, uniconazole, and paclobutrazol were applied as a drench at various concentrations. In Oriental hybrid lily 'Rialto', no changes were observed not only plant height but also leaves and flowers in paclobutrazol treatment. But the growth of plant treated with ancymidol was inhibited above 30% compare to control regardless of concentrations. However, numbers of leaf and flower per plant were similar to those of controls. Plant height was similar to nontreated control in $1mg{\cdot}L^{-1}$ uniconazole treatment but that reduced about 30% in drench application of 5 and $10mg{\cdot}L^{-1}$ uniconazole. Asiatic hybrid lily 'Elodie' was not different in growth between application of paclobutrazol and nontreatment as 'Rialto'. While, in all ancymidol treatments, plant height was 50~60% shorter than that of control. Also, numbers of leaves were reduced and days to flowering were slightly delayed in $30mg{\cdot}L^{-1}$ ancymidol treatment as compared with the control. All traits except plant height of $1mg{\cdot}L^{-1}$ uniconazole were similar to control but there were differences of statistical significance between 5, $10mg{\cdot}L^{-1}$ uniconazole drench and nontreated control. Lilium ${\times}$ formolongi 'Raizan' like above two cultivars had no dwarf effect on height in paclobutrazol treatment. In drench application of ancymidol, plant height reduced over 60% than that of control regardless of concentrations. Especially, days to flowering were a little delayed with $30mg{\cdot}L^{-1}$ paclobutrazol treatment. Plant height of $10mg{\cdot}L^{-1}$ uniconazole was about 26% shorter than that of control, but other traits were no differences between uniconazole treatment and control. In result, the drench application of ancymidol and uniconazole was pretty effective for usage as pot lily without great changes of quantitative traits.

Growth and Flowering of Campanula Species as Affected by Duration, Temperature, and Light Condition during Chilling Treatment (저온처리 기간, 온도 및 광 조건이 자생초롱꽃의 생육과 개화에 미치는 영향)

  • Lee, Young Mi;Park, Yoo Gyeong;Jeong, Byoung Ryong
    • FLOWER RESEARCH JOURNAL
    • /
    • v.19 no.1
    • /
    • pp.22-29
    • /
    • 2011
  • The experiment investigated effect of duration, temperature, and light condition during chilling treatment on growth and flowering of four Campanula species in a factorial experiment. Two parent species, Campanula punctata Lam. var. rubriflora Mak. and C. Punctata Lam., and their two $F_1$ hybrids, C. punctata Lam. ${\times}$ C. punctata Lam. var. rubriflora Mak. ('Jiknyeo') and C. punctata Lam. var. rubriflora Mak. ${\times}$ C. punctata Lam. ('Gyeonu'), were used. Plants were cultured in vitro for five weeks at $25^{\circ}C$ under about $75{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD before being chilled at 4 or $25^{\circ}C$ for 3, 6, or 9 weeks under a darkened or lighted (about $10{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD) condition. After chilling treatment, plants were transplanted to 10 cm pots filled with a commercial growing medium and were transferred to environment-controlled growth chambers and subsequently to a greenhouse to observe their reproductive growth. Growth of all species and flowering of a $F_1$ hybrid 'Jiknyeo' were affected by duration, temperature, and light condition during chilling treatment. The greatest growth and survival percentage were observed in C. punctata Lam. var. rubriflora Mak. The survival percentage was greater when plants were chilled in a lighted than darkened condition, whereas it decreased when plants were chilled more than six weeks in vitro. Among the four species tested, flowering was observed only in a $F_1$ hybrid 'Jiknyeo' with 62.5% flowering plants when it was chilled at $25^{\circ}C$ for three weeks under a lighted condition. Percent flowering plant was affected by duration, temperature, and light condition during chilling treatment. Three-week chilling at $4^{\circ}C$ under a darkened condition significantly reduced days to flowering. These results suggest that the low temperature requirement for flowering is not qualitative but quantitative in Campanula species. Further experiment with more number of plants is necessary to ascertain this conclusion.

Effluent Characteristics of Nonpoint Source Pollutant Loads at Paddy Fields during Cropping Period (영농기 광역논으로부터 비점오염물질 유출 특성)

  • Han, Kuk-Heon;Kim, Jin-Ho;Yoon, Kwang-Sik;Cho, Jae-Young;Kim, Won-Il;Yun, Sun-Gang;Lee, Jeong-Taek
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.40 no.1
    • /
    • pp.18-24
    • /
    • 2007
  • Paddy fields are apparently nonpoint source pollution and influence water environment. In order to improve water quality in rivers or lakes, to low nutrient load from paddy fields are required. To establish comprehensive plan to control agricultural non-point source pollution, it is imperative to get a quantitative evaluation on pollutants and pollution load from paddy fields. A field monitoring study was carried out to investigate the water balance and losses of nutrients from fields in Sumjin river basin. The size of paddy fields was 115 ha and the fields were irrigated from a pumping station. The observed total nitrogen loads from paddy fields were larger than those of the unit loads determined by Ministry of Environment data (MOE). It is because the nitrogen fertilization level at the studied field was higher than the recommended rate and the high irrigation and subsequent drainage amount. On the contrary, total phosphorus loads were less than those addressed by MOE since phosphorus fertilization level was lower than that of standard level. Therefore, it was found that fertilization, irrigation, and drainage management are key factors to determine nutrient losses from paddy fields. When the runoff losses of nutrients were compared to applied chemical fertilizer, it was found that 42 to 60% of nitrogen lost via runoff while runoff losses of phosphorus account for 1.3 to 7.6% of the total applied amount during the entire year.