• Title/Summary/Keyword: c.d.f

Search Result 2,587, Processing Time 0.036 seconds

THE LORENTZ FORCE IN ATMOSPHERES OF CP STARS: θ AUR

  • VALYAVIN G.;KOCHUKHOV O.;SHULYAK D.;LEE B.-C.;GALAZUTDINOV G.;KIM K.-M.;HAN I.
    • Journal of The Korean Astronomical Society
    • /
    • v.38 no.2
    • /
    • pp.283-287
    • /
    • 2005
  • The slow evolution of global magnetic fields and other dynamical processes in atmospheres of CP magnetic stars lead to the development of induced electric currents in all conductive atmospheric layers. The Lorentz force, which results from the interaction between a magnetic field and the induced currents, may modify the atmospheric structure and provide insight into the formation and evolution of stellar magnetic fields. This modification of the pressure-temperature structure influences the formation of absorption spectral features producing characteristic rotational variability of some spectral lines, especially the Balmer lines (Valyavin et al., 2004 and references therein). In order to study these theoretical predictions we began systematic spectroscopic survey of Balmer line variability in spectra of brightest CP magnetic stars. Here we present the first results of the program. A0p star $\Theta$ Aur revealed significant variability of the Balmer profiles during the star's rotation. Character of this variablity corresponds to that classified by Kroll (1989) as a result of an impact of significant Lorentz force. From the obtained data we estimate that amplitudes of the variation at H$\alpha$, H$\beta$, H$\gamma$ and H$\delta$ profiles reach up to $2.4\%$during full rotation cycle of the star. Using computation of our model atmospheres (Valyavin et al., 2004) we interpret these data within the framework of the simplest model of the evolution of global magnetic fields in chemically peculiar stars. Assuming that the field is represented by a dipole, we estimate the characteristic e.m.f. induced by the field decay electric current (and the Lorentz force as the result) on the order of $E {\~} 10^{-11}$ cgs units, which may indicate very fast (< < $10^{10}$ years) evolution rate of the field. This result strongly contradicts the theoretical point of view that global stellar magnetic fields of CP stars are fossil and their the characteristic decay time of about $10^{10}$ yr. Alternatively, we briefly discuss concurring effects (like the ambipolar diffusion) which may also lead to significant atmospheric currents producing the observable Lorentz force.

An Analysis of Inquiry Activities in Chemistry II Textbook by Using 3-Dimensional Analysis Framework (3차원 분석틀을 이용한 화학II 교과서의 탐구활동 분석)

  • Seok Hee Lee;Yong Keun Kim;Seong Bae Moon
    • Journal of the Korean Chemical Society
    • /
    • v.47 no.4
    • /
    • pp.391-400
    • /
    • 2003
  • This study was performed the analysis of seven kinds of the hight school chemistry II textbooks based on the 6th curriculum. Particularly, inquiry activity part was analyzed by the three dimension framework which consists of inquiry content dimension, inquiry process dimension and inquiry context dimension. In the analysis of the inquiry content dimension of inquiry activities, the total number of themes in seven kinds of textbook was 212. And the number of inquiry activities in seven kinds of textbook was diverse: A textbook had 28, B textbook 25, C textbook 31, D textbook 35, E textbook 31, F textbook 29 and G textbook 33. As for the avaerage number of inquiry activities of each chapter, chapter I "Material Science" is 3.00(9.91${\%}$), chapter II "Atomic Structure and Periodic Table" 4.57(15.1${\%}$), chapter III "Chemical Bonding and Compound" 6.86(22.6${\%}$), chapter IV "State of Matter and Solution" 7.00(23.1${\%}$), chapter V "Chemical Reaction" 8.86(29.2${\%}$). For the analysis of inquiry process dimension, it follows in the order of 'observation and measuring (66.7${\%}$)', 'Interpreting data and formulating generalizations (26.5${\%}$)', 'seeing a problem and seeking ways to solve it (4.1%)', and 'building, testing and revising the theoretical model (2.7${\%}$)'. As for the analysis of the inquiry context dimension, the scientific context occupied 90.5${\%}$, the individual context 4.3${\%}$, the social context 0.9${\%}$, and the technical context 4.3${\%}$. It shows that the proportion of STS(Science-Technology-Society) related contents in inquiry activities was only 9.5${\%}$.

School Phonetics and How to Teach Prosody of English in Japan

  • Tsuzuki, Masaki
    • Proceedings of the KSPS conference
    • /
    • 1997.07a
    • /
    • pp.11-25
    • /
    • 1997
  • This presentation will focus on building basic English Prosodic Skills which are very useful and helpful for Japanese learners of English. The focus first will be on recognizing the seven basic nuclear tones, analysing intonation structures, distinguishing intonation patterns and then on the way of improving speaking ability using sufficient verbal contents of intonation (mini-dialogue). My presentation deals mainly with some difficulties which Japanese learners of English have in the field of RP intonation, It is chiefly concerned with identifying, describing and analysing tone-group sequences. It sometimes happens that Japanese learners of English can pronounce isolated bounds correctly and read phonetic symbols sufficiently, bet have difficult problems in carrying out accurate prosodic features. The use of wrong intonation is sometimes the cause of misunderstanding of speaker's attitude, connotation and shades of meaning, etc.. However accurately students can pronounce the nuclear tone or tone-group of English, they have to learn how to connect tone-groups properly for suitable sequences in respect to meaning or implication. We are faced with the complicated theory of RF intonation on the one hand and difficult realization of it on the other. Japanese learners of English have special difficulties in employing "rising tune" and "falling + rising tune". If students are taught pitch movements by indicating dots graphically between two horizontal lines, they can easily understand the whole shape of pitch movements. In this presentation, I illuminate several tone-group sequences which are very useful for Japanese learning English intonation. Among them, four similar Pitch Patterns, such as, (1) (equation omitted)- type, (2) (equation omitted) - type, (3) (equation omitted) - type and (4) (Rising Head) (equation omitted)- type are clarified and other important tone-group sequences aye also highlighted from the point of view of teaching English as a foreign language. The intonation theory, tone marks and technical terms are, in all essentials, those of Intonation of Colloquial English by O'Connor, J. D. and Arnold, G. F., Longman, 2nd ed., 1982. The changes of tone are shown graphically between two horizontal lines representing the ordinary high and low zones of the utterance. A.C.Gimson (1981:314) : The intonation of English has been studied in greater detail and for longer than that of any other language. No definitive analysis, classifying the features of RP intonation, has yet appeared (though that presented by O'Connor and Arnold (1973) provides the most comprehensive and useful account from the foreign learner's point of view).

  • PDF

A Study on the Effects of the X-Ray Irradiation and Thyroid Gland on the Erythropoietic System in Rabbit (가토(家兎)에 있어서 방사선조사(放財線照射)와 갑상선(甲狀腺)이 조혈계(造血系)에 미치는 영향(影響)에 관(關)한 연구(硏究))

  • Kim, Kong-Keun
    • The Korean Journal of Nuclear Medicine
    • /
    • v.1 no.1
    • /
    • pp.1-19
    • /
    • 1967
  • The effects of X-ray irradiation and the thyroid gland on the erythropoietic system were studied in the white male rabbits. The total body irradiation was done in doses of 250 r and 500 r to each of 5 rabbits for 10days. The factors were 220KV, 10mA, FLI/4 Cu+1 mmAI(HVL:2.0 mm Cu) 50 cm F.S.D. The thyroid dysfunction was experimentally induced, by giving 2mg of thyroid tablets per kg body weight for 15 days in 5 rabbits for hyperthyroidism and by giving 1.5 mC of $^{131}I$ per kg body weight in another 5 rabbits for hypothyroidism. Fourteen healthy rabbits were used as control. The hematologic changes and ferrokinetic data obtained from $^{59}Fe$ and apparent half survival of the red blood cells obtained from $^{51}Cr$ were compared. Following were the results: A. X-ray irradiated group; 1. There were no significant changes in hematologic findings except for leucopenia. A slight decrease of red blood cells was observed in 500 r irradiated animals. 2. The decreases in the iron turnover rates of the plasma and red blood cells as well as in the red cell renewal rate were found in both groups. A :significant decrease of the red cell iron utilization rate was observed in the 500 r irradiated animals. 3. The apparent half survival times of the red blood cells were slightly, in the 250 r ($12.1{\pm}0.80$ days), and markedly shortened in the 500 r irradiated animals ($9.8{\pm}1.38$ days), the normal being $14.0{\pm}1.6$ days. 4. It appears, therefore, that the anemia caused by X-ray irradiation is due to the inhibition of hemopoietic function and the excess destruction of the red blood cells. B. Thyroid dysfunction group; 1. The slight increases of the red blood cell count and circulating blood volume with the normal serum iron level were observed in the hyperthyroid group, while the decreases of the red and white blood cell counts, hemoglobin and hematocrit values with a marked decrease of the serum iron level in the hypothyroid group. 2. A marked decrease of the plasma iron disappearance rate with increases of plasma iron turnover, red cell iron utilization and red cell iron turnover were observed in the hyperthyroid group, while the marked delay and decreases in the hypothyroid group. 3. The apparent half survival times of the red blood cells were almost the same with the control in the hyperthyroid group, ($14.0{\pm}1.58$ while a marked shortening in the hypothyroid group $10.6{\pm}0.30$. 4. It was reconfirmed that the thyroid hormones bear a close relationship with the erythropoietic system, namely, the latter is stimulated by the former. The lack of the thyroid hormones thus induces the bone marrow depression leading to anemia the major cause of which, therefore, is not hemolysis.

  • PDF

Studies on the Fatty Acid Composition of Amorpha-fruticosa Seeds (Amorpha-fruticosa종자(種子)의 지방산조성(脂肪酸組成)에 관한 연구(硏究))

  • Whang, Byung-Ho;Lee, Sang-Young
    • Korean Journal of Food Science and Technology
    • /
    • v.6 no.2
    • /
    • pp.86-90
    • /
    • 1974
  • Quantitative analysis of the fatty acids contained in Amorpha-fruticosa seeds was carried out by means of gas chromatography with F.I.D. The general components and chemical constants have been performed with A.O.A.C methods. The results are summarized as follow: 1. General components of Amorpha-fruticosa seeds come out to be 17.65% moisture, 21.02% crude protein, 12.04% crude lipid and 5.37% ash. 2. Extraction of crude lipids were performed by soxhlet extractor for 14 hour. Amounts of the crude lipids were extracted 80.25% in ether, 80.00% in methanol, 77.34% in benzene and 69.96% in hexane. 3. Chemical constants of Amorpha-fruticosa seed oil were saponification number 178.67, acid number 3.11 and iodine number 54.27. 4. The fatty acid components of Amorpha-fruticosa seeds were quantitatively determined by gas chromatography to give 78.73wt% linoleic, 5.8wt% oleic, 5.68wt% palmitic, 4.8wt% stearic and 3.40wt% linolenic acid in ether solvent and to give 77.86wt% linoleic, 7.77wt% palmitic, 5.84wt oleic and 4.97wt% stearic acid in methanol solvent. The peak of capric acid was not found. Myristic, arachidic and lauric acids were very small.

  • PDF

Prediction of Optimum Fertilizer Rate for Flue-Cured Tobacco by Nitrogen Availability in Soils (토양질소(土壤窒素)의 유효도(有效度) 검정방법(檢定方法)에 의한 황색종연초(黃色種煙草)의 적정시비량(適正施肥量) 추정(推定))

  • Jeong, Hun-Chae;Cho, Seong-Jin;Hong, Sun-Dal;Lee, Yun-Hwan
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.18 no.2
    • /
    • pp.169-176
    • /
    • 1985
  • Six analytial methods for determing the available nitrogen in soils were tested to predict the optimum fertilizer rate for the flue-cured tobacco and to test the fertility level of soils for tobacco. All methods, nitrifiable $NO_3-N$ value for 2 and 4 weeks incubation, UV absorption value at 260nm and N-value in acid digestion of 0.01 M-$NaHCO_3$ extracts, N-value extracted in boiling with $CaCl_2$ solution, and autoclave-extractable $NH_4-N$ value in 0.01 M-$CaCl_2$, were closely correlated with total nitrogen uptake as well as yield. Therefore available nitrogen indices determined from above 6 analysis method could be used for the predicting of tobacco yield without fertilizer, criteria for fertility class, and recommendable range of optimum fertilization.

  • PDF

Production of Korean Native Cow from Mongolian Cow following Transfer of Vitrified Blastocyst (Mongolian 수란우에 한우 동결수정란의 이식 후 산자 생산)

  • Kong, I.K.;Sanjjav, G.;Yang, C.J.;Cho, S.G.;Bae, I.H.;Oh, D.H.
    • Journal of Embryo Transfer
    • /
    • v.17 no.2
    • /
    • pp.129-136
    • /
    • 2002
  • The purpose of this study was to investigate the comparison of viability of bovine blastocysts following glass micropipette (GMP) vitrification and the possibility of production of Korean Native Cow ("Hanwoo,"Bos taurus coreanae) following embryo transfer into Mongolia cows (Bos taurus mongolian). The embryos of Korean Native Cow were produced by IVMFC or superovulation methods in Korea, cryopreserved by GMP vitrification, and subsequently trans-ported to Mongolia. The recipient cows were synchronized using a CIDR plus and prostaglandin $F_2\alpha$($PGF_2\alpha$) treatment. To produce in vivo embryos, seven cows were superovulated using FSH and PGF$_2$/sub $\alpha$/ treatment. A total of 64 blastocysts ( $9.1\pm2.94$ per cow) were collected. In vitro embryos were produced using a defined culture system which cleaved in 80.1% ova (174/217), and developed to blastocyst stage embryos of 40.8% (71/174). The post-thaw survival rate of in vivo blastocysts (93.7%; 45/48) was significantly higher than that of in vitro blastocysts (82.5%; 52/63, P<0.05). Embryo transfer was carried out using 8 Mongolian recipient cows and 2 post-thaw blastocysts per recipient. Five of 8 recipients were found pregnant at Day 60 but one abortion occurred by Day 240. Two of offspring were produced from the Mongolian cows at 275 days after embryo transfer. These results indicated that a GMP vitrification method could be used as a cryopreservation technique for in vivo or in vitro bovine blastocysts and produced effectively a Korean Native Cow following embryo transfer into a Mongolian recipient cow.

Shift in Weed Occurrence Accompanied Type of Direct - seeded Rice Fields (벼 직파재배(直播栽培) 유형별(類型別) 잡초발생(雜草發生)의 변화(變化))

  • Choi, C.D.;Won, J.G.;Lee, W.H.;Choi, B.S.
    • Korean Journal of Weed Science
    • /
    • v.17 no.2
    • /
    • pp.139-146
    • /
    • 1997
  • The experiment was conducted at Gyeongbuk Provincial Rural Development Administration in 1996 to obtain basic information on weed ecology and effective weed control in direct-seeded rice fields under different seeding types and seeding times. A large number of upland weeds such as Echinochloa crus-galli, Digitaria sanguinalis, Capsella bursa-pastoris and Stetaria viridis etc occurred at early growth stage, while Eleocharis kuroguwai, Aneilema keisak and Cyperus serotinus dominated at late stage in dry seeded rice field. In wet seeded rice field, the dominance of E. crus-galli was lower and the occurrence of M. vaginalis and A. keisak were higher than in dry seeded field. Amount of weed occurrence in dry seeded field was 1.8 to 2.4 times greater than in wet seeded field and it increased with delaying seeding time. Increasing rate of weed occurrence through whole life cycle was the highest at 20 days after seeding (DAS) to 40 DAS, regardless of seeding types and seeding times. Simpson index in wet seeded field was higher than in dry seeded field and it gradually increased as growing of dominant species. For F-value test, it was recognized as statistical significant in seeding types, seeding times and interaction of two factors.

  • PDF

Production and Action of Microbial Piscicidal Substance (미생물에 의한 살어성물질의 생성 및 그 작용)

  • 도재호;서정훈
    • Microbiology and Biotechnology Letters
    • /
    • v.6 no.1
    • /
    • pp.41-46
    • /
    • 1978
  • Piscicidal substance produced by Streptomyces sp. isolated from soil was toxic against various kinds of fish. After extraction with CH$Cl_3$ from the culture medium, the substance was purified by avicel column chromatography. In order to test toxicity, various kinds of fish were subjected to the acqueous solution of 100 us of the substance per liter of water. Generally, the substance was toxic to most fish, but Macropodus chinenes and Misgurnus mizolepis are resistant to the substance than Gobius similis and Pseudorasbora parva. The substance was stable at pH range, 3.0 to 7.0, but labile at alkaline pH, and to heat as well. Succinic dehydrogenase on most of tissue cell of Cyprinus carpio was inhibited by this substance strongly, but spinal cord was not inhibited. By addition of Cu and Pb salts to the culture medium, piscicidal substance producibility was activated.

  • PDF

A Study on the Perceived Symptoms of Fatigue of the Workers in the Textile Industry (일부 섬유 제조업 근로자의 피로자각 증상에 관한 연구)

  • Suh In Sun;Ahn Ok Hee
    • Journal of Korean Public Health Nursing
    • /
    • v.7 no.1
    • /
    • pp.81-97
    • /
    • 1993
  • This study was carried out to analyze the factors of the perieved symptoms of fatigue of the industrial workers, to examine the inter-relatisnship of the above factors with their general charactenstics and the environments of working area for the examination of their health status and the effective health management of them. This study was undertaken from December 1 to December 20, 1990. The subjets were 495 workers who had worked at the Industrial complex located in Chonbuk Province. The result of this study were as follows: 1. The worker's percieved symptoms of fatigue were classified to the following seven factors; A) Musculo-Skeletal Symptoms, B) Neuro-Psychial Symptoms, C) Optical Symptoms, D) Heart Symptoms, E) Head Symptoms, F) Respiratory Symptoms, G) Genital Symptoms 2. Analysis of the inter-relationship of their percieved symptoms of fatigue with general characteristics; 1) The difference of distribution to their percieved symptoms of fatigue according to sexuality was significant; Female were higher than Male $(p{\leqq}0.001$, p<0.005) 2) The difference of distribution to their percieved symptoms of fatigue according to age was significant; Age group under 24 years of age were higher than the other's group (p<0.001). 3) The difference of distribution to their percieved symptoms of fatigue according to the level of education was significant; Workers who stand on a low intellectual were higher than workers on a high intellectual level. 4) The difference of distribution to their percieved symptoms of fatigue for a week was the highest when worked at sunday. 5) The difference of distribution to their percieved symptoms of fatigue for seasons was high at spring. 3. Analysis of the inter-relationship of their percieved symptoms of fatigue with the environments of working area. 1) The difference of distribution of their percieved symptoms of fatigue according to the working department was significant; Production workers were higher than office workers. 2) The difference of distribution of their percieved symptoms of fatigue related with working posture was significant; Sitting: Musculo-Skeletal symptoms (p<0.05), Optical symptoms (p<0.005) 3) The more dissatisfied with their's own duty they were, the higher became the distribution of their percieved symptoms of fatigue (p<0.001. p<0.005, p<0.05) 4) The more dissatisfied with their working condition they were, the higher became the degree of their percieved symptoms of fatigue (p<0.001. P<0.05) 5) The difference of distribution of their percieved symptoms of fatigue according to kinds of job was significant: Workers who has handled heavy materials were higher than who had not handled $(p{\leqq}0.001$, p<0.05). Workers who has handled chemical materials: Optical, symptoms $(p{\leqq}0.001)$. Workers who has handled dusty materials: Respiratory symptoms (p<0.01) 6) The environment of working area was significantly affected to the distribution of their percieved symptoms of fatigue: Workers complains of a illumination problem; Optical symptoms (p<0.005), Heart symptoms (p<0.005) Workers complains of a ventilation problem: Heart symptoms (p<0.05), Optical symptoms, Heart symptoms (p<0.01) Musculo-skeletal symptoms ($p{\leqq}0.001$)

  • PDF