• Title/Summary/Keyword: Percent contrast

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A Study on the Effect of Chemicals on the Survival Rate and the Metamorphosis Speed in Rana nigromaculata Hallowell. (수종의 약품이 개구리의 생존율과 변태속도에 미치는 영향에 관한 연구)

  • 한양일;조소남
    • Journal of Environmental Health Sciences
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    • v.5 no.1
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    • pp.66-70
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    • 1978
  • This experiment is to search what some chemicals polluting water have an effect on the Rana nigromaculata Hallowell, in the survival rate and the metamorphosis speed from a tadpole to a young frog. 1. The fatal thickness by some agricultural chemicals and copper sulfate is different from one another. The fatal rate in the contrast group is 15 percent, and particulary Dithane M-45 is the most among the all reagents. 2. The effect on the anamorphosis is very severe. In the case of contrast group, it appears to stage 25, but it is not to appear at the group used agricultural chemicals. 3. The less the thickness of that is, the less the influence of the survival rate and the metamorphosis speed. 4. The density of the agricultural chemical is in inverse proportion to the survival rate and the metamorphosis speed, and the other side, the fatal rate is proportion.

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Medkum TAu Inversion Recover(MTIR) Sequence for White Matter Suppression in Brain Cortical Lesions (뇌피질 질환에서 뇌백질 신호 억제를 위한 중간시간 반전회복 영상 기법)

  • 정경호;이정민;김종수
    • Investigative Magnetic Resonance Imaging
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    • v.3 no.1
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    • pp.60-65
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    • 1999
  • Purpose : The purpose of this study was to evaluate the image quality, contrast characteristics, and possible clinical utility of Medium Tau Inversion Recovery(MTIR) sequence with white matter suppression in patients with brain cortical lesion. Materials and methods : Two normal volunteers and twenty-one patients with cortical lesion were scanned with MTIR as well as other MR imaging sequences. Gray-white matter contrast was evaluated objectively using region-of-interest calculations, including percent contrast and contrast-to-noise ratio(CNR). MTIR sequence was visually compared with other sequences in 21 patients with cortical lesion including conspicuity and detection rate. Results : MTIR sequence had the highest present contrast and CNR between the gray matter and white matter. In twenty-one cases of cortical lesion including cortical dysplasia, MTIR sequence improved delineation and conspicuity of lesion, but MTIR sequence could not detect new lesions. Conclusion : The MTIR sequence well delineated the cortical lesions, particularly in including cortical dysplasia. It may be used as an adjunctive imaging sequence in case of poor gray and white matter differentiation with conventional T1-weighted sequences.

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A Study on the Characteristics of Dye Sensitized Solar Cells with TiO2 Thickness and Sintering Temperature (TiO2 두께 및 소성온도에 따른 염료감응 태양전지 특성에 관한 연구)

  • Lee, Young-Min;Lee, Don-Kyu
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.9
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    • pp.1233-1238
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    • 2014
  • In this thesis, it is investigated the characteristics of Dye Sensitized Solar Cell (DSSC) according to variation of $TiO_2$ thickness (6, 12, 18, and $24{\mu}m$) and three distinct $TiO_2$ sintering temperatures (350, 450 and $550^{\circ}C$) by XRD, SEM, I-V and UV-Vis spectrophotometer. According to sintering temperature, $TiO_2$ was transformed into the anatase structure at $350^{\circ}C$, rutile structure at $550^{\circ}C$ and further into the two structure at $450^{\circ}C$. With increasing thickness up to $18{\mu}m$ and sintering temperature up to $450^{\circ}C$, respectively, the irradiance rate increased in the range of 9~26 percent and 2.80~5.10 percent. Whereas a further increase to $24{\mu}m$ and $550^{\circ}C$, the irradiance rate decrease in the range of 4~11 percent and 30~47 percent. The conversion efficiency increased in the range of 2.80~5.01 and 3.03~5.01 with increasing thickness up to $18{\mu}m$ and sintering temperature up to $450^{\circ}C$. By contrast, increase to $24{\mu}m$ and $550^{\circ}C$, the conversion efficiency decreased in the range of 3.31~5.01 and 2.80~3.89, respectively. The DSSC that thickness of $TiO_2$ were $18{\mu}m$ and sintered at $450^{\circ}C$ exhibited the most excellent characteristics, in which open-circuit voltage, short-circuit current, Fill Factor and conversion efficiency are 0.69 V, $11.4mA/cm^2$, 0.64 and 5.01%, respectively.

The relationship between % Body Fat and Blood Pressure, Total Cholesterol, and Serum Lipoprotein Ratios in College Students (대학생의 체지방 수준과 혈압, 총콜레스테롤 및 혈청 지단백비율과의 관계)

  • 김영수
    • Korean Journal of Health Education and Promotion
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    • v.15 no.1
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    • pp.195-204
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    • 1998
  • The purpose of this study was to develop cardiovascular health related percent body-fat standards that may be applied to epidemiologic investigations of the prevalence and incidence of obesity in adolescents, pediatric health screenings, and youth fitness tests. The subjects included 102 males and 80 females aged 19~22years. All subject were Honam University Students Total body fat was derived from body density which was estimated from age and the triceps and subscapular skinfold thickness measured with Lang calipers to the nearst l.0mm. Serum total cholesterol and lipoprotein cholesterol fraction(HDL-CLDL-C) were measured from blood obtained from fore arm vein after blood pressure measurement. In analyses to determine critical fat levels associated with elevated CDD(Chronic Degenerative Disease) risk factors;male and female were grouped by level of percent fat as follows: male, 〈 10%, 10-14.9%, 15-19.9%, 20-24.9%, and $\geq$ 25%;female, 〈 20%, 20-24.9%, 25-29.9%, 30-34.9%, and $\geq$ 35%. As the results of the data, the conclusions were as follows: 1. A dose respones effect was observed between blood pressure and percent body fat in males and females; in contrast, total cholesterol and lipoprotein ratios were relatively independant of percent fat among the lower four fatness group in males and the lower three fatness groups in females. 2. The percentage of subjects in the uppermost quintile for S-Bp, D-Bp, TC, LDL/H was significantly(P〈.05) greater than expected by change alone(20%) in males with $\geq$ 25% fat and in females with $\geq$ 30% fat females with $\geq$35% had even greater representation in the uppermost quintile of all CDD risk factors compared to females with 30-34.9% fat.

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Catalog use study : with reference to universities in Daegu (대학도서관의 목록이용연구)

  • 최달현
    • Journal of Korean Library and Information Science Society
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    • v.9
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    • pp.241-266
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    • 1982
  • This paper gives a summary and overview of a survey conducted at the catalogues of five universities in Daegu during November 1982. The major objective of this study was to secure information about user needs in order to improve the catalogue in Korean university libraries. Data was collected by a combined method of questionnaire and interview. A total of 379 respondents were taken on a randomly selected sample of catalogue users. Results of the survey can be summarized as follows: 1. Eighty-eight percent of the students answered that they had used the library more than twice a month. Nevertheless the number of students consulting the catalogue with the same frequency was only 220, or a n.0, pproximately 58 percent. Those who used the library most tended to use the catalogue more than those who rarely came to the library. 2. Those who had been shown how to use their own catalogue were only 32.5percent of which the students found the instruction sufficient for them to be able to use the catalogue were only 37.5 percent. In particular, they stated that instructions by printed materials and/or library orientation were so poor that they didn't give much help in using the catalogue. This problem makes many libraries to review their own method of instruction in order to encourage patrons to use the catalogue more effectively. 3. Most of the students consulted the catalogue in order to locate library materials. Known-item searches and subject searches were 84 and 16 percent respectively. While 70.5 percent of the students used the author-title catalogue without any difficulties, only 35.5 percent of those stated that using the classed catalogue was easy. 4. It was surprising that the number of students using title access in the search was far greater than that of students using author access. In contrast with this, other studies conducted by many earlier overseas investigators revealed that the great majority of patrons tended to use the latter first. Therefore, we should put more emphasis on the title entries in the catalogue itself as well as cataloging rules. 5. Most useful bibliographic elements in the entry were author, title, call number, date and publisher whereas edition, series statement and the location of publisher were rarely used compared with the other elements. Content note was the most desirable element in the entry to be involved, for many catalogers were used not to describe it on the note area. 6. The chief reason given for not using the catalogue was "I can manage without it" with "It's difficult to understand contents of the card entry." The other one was "It's useless to search materials by the catalogue because I've failed so many times to obtain them out of the stock." In response to this, circulation and acquisition system should be improved not to make such complaints any more.

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Market Oriented Revenue Assistance for Farmers: A Case Study of the United State's ACRE Program

  • Zulauf, Carl;Rhew, Chan-Hee;Kim, Sang-Hyo
    • Journal of Distribution Science
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    • v.14 no.11
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    • pp.29-36
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    • 2016
  • Purpose - Intense debate is occurring over support for farmers in Korea, specifically on the justification, policy design, and equality issues of the farm support programs. Given this debate, a new type of farm program in the US, a market flexible revenue program(the Average Crop Revenue Election, ACRE), is examined. ACRE stands in contrast to traditional programs that tie payments to price and have parameters that are fixed or change only infrequently. Research design, data, and methodology - Based on the ACRE program formulas, the potential payments are estimated by crop year, program crop and geographical area using the FSA acreage and payment rate data. Results - If all US farm program acres were in ACRE over the 2009-2013 crop years, payments would have totaled $7.95 billion or 1.2 percent of average market receipts for US crops. Enacting ACRE as a revenue program instead of a similarly-structured price-only program increased payments by $1.75 billion or 28 percent. Conclusions - Potential payments by ACRE largely reflected the distribution of the value of production across the program crops eligible for ACRE as well as across state geographical areas. If program parameters can be made acceptable and if data availability issues can be addressed, market flexible revenue programs offer a farm policy option that can address many of the concerns that have arisen over farm policy in Korea.

Electrical Characteristics of Solution Processed In-Ga-ZnO Thin Film Transistors (IGZO TFTs) with Various Ratio of Materials

  • Lee, Na-Yeong;Choe, Byeong-Deok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.293.2-293.2
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    • 2016
  • The In this paper, we have fabricated the solution processed In-Ga-ZnO thin film transistors (IGZO TFTs) by varying indium and gallium ratio. The indium ratio of IGZO TFTs was changed from 1 to 5 at fixed gallium and zinc oxide atomic percent of 1:1 and gallium ratio was varied from 1 to 5 at fixed indium and zinc oxide atomic percent of 1:1. When the indium ratio was increased at fixed gallium and zinc oxide ratio of 1:1, threshold voltage was negatively shifted from 1.03 to -6.18 V and also mobility was increased from 0.018 to $0.076cm2/V{\cdot}sec$. It means that the number of carriers in IGZO TFTs were increased due to great formation of the oxygen vacancies which generate electrons. In contrast, when the gallium ratio was increased in IGZO TFTs with indium and zinc oxide ration of 1:1, the on/off current ratio was increased from $1.88{\times}104$ to $2.22{\times}105$. It is because gallium have stronger chemical bonds with oxygen than that with the zinc and indium ions that lead to the decreased in electron concentration.

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Behavior of Tip Vortex in a Propeller Fan (프로펠러팬에서의 Tip Vortex 거동)

  • Kim, Sung-Hyup;Furukawa, Masato;Inoue, Masahiro
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.1377-1382
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    • 2004
  • Flow fields in a half ducted propeller fan have been investigated by three-dimensional Reynolds-averaged Navier-Stokes (RANS) simulations and a vortex core identification technique. The simulation at the design operating condition shows that the tip vortex onset point is located at 30 percent tip chord of the suction surface on the blade tip. There is no interaction between the tip vortex and the adjacent blade, so that the tip vortex smoothly convects to the rotor exit. However, the high vorticity in the tip vortex causes the wake and the tip leakage flow to be twined around the tip vortex and to interact with the pressure surface of the adjacent blade. This flow behavior corresponds well with experimental results by Laser Doppler Velocimetry. On the contrary, the simulation at the low-flowrate operating condition shows that the tip vortex onset point is located at the 60 percent tip chord of the suction surface. In contrast to the design operating condition, the tip vortex grows almost tangential direction, and impinges directly on the pressure surface of the adjacent blade.

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Resonance Elastic Scattering and Interference Effects Treatments in Subgroup Method

  • Li, Yunzhao;He, Qingming;Cao, Liangzhi;Wu, Hongchun;Zu, Tiejun
    • Nuclear Engineering and Technology
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    • v.48 no.2
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    • pp.339-350
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    • 2016
  • Based on the resonance integral (RI) tables produced by the NJOY program, the conventional subgroup method usually ignores both the resonance elastic scattering and the resonance interference effects. In this paper, on one hand, to correct the resonance elastic scattering effect, RI tables are regenerated by using the Monte Carlo code, OpenMC, which employs the Doppler broadening rejection correction method for the resonance elastic scattering. On the other hand, a fast resonance interference factor method is proposed to efficiently handle the resonance interference effect. Encouraging conclusions have been indicated by the numerical results. (1) For a hot full power pressurized water reactor fuel pin-cell, an error of about +200 percent mille could be introduced by neglecting the resonance elastic scattering effect. By contrast, the approach employed in this paper can eliminate the error. (2) The fast resonance interference factor method possesses higher precision and higher efficiency than the conventional Bondarenko iteration method. Correspondingly, if the fast resonance interference factor method proposed in this paper is employed, the $k_{inf}$ can be improved by ~100 percent mille with a speedup of about 4.56.

A Study on Red Cell Protoporphyrin Concentration and Iron Metabolism (적혈구(赤血球) Protoporphyrin과 철분대사(鐵分代謝)에 관(關)한 연구(硏究))

  • Cho, Kyung-Hwan;Tchai, Bum-Suk
    • Journal of Nutrition and Health
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    • v.7 no.3
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    • pp.1-13
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    • 1974
  • The relative state of human iron storage may be ascertained more reliably through determination of the serum iron, iron binding capacity, transferrin saturation and absorption of radioactive iron in conjunction with studies of red cell morphology than from the study of red cell morphology alone. Recent investigations have shown that there is an increase in red cell protoporphyrin concentration in iron deficiency anemia. The significance of the red cell protoporphyrin has been discussed greatly during the years since its discovery. Two of the main factors which appear to influence the amaunt of protoporphyrin are increased erythropoiesis and factors interfering with the utilization of iron in the synthesis of hemoglobin, and iron deficiency. Recently Heller et al. have described a simplified method for blood protoporphyrin assay and this technique could be used assess nutritional iron status, wherein even minor insufficiencies are detectable as increased protoporphyrin concentrations. Based on the evaluation of the relationship between nutritional iron status and red cell protoporphyrin as an index suitable for the detection of the iron deficiency is described in this paper. RESULTS 1. Hemoglobin Concentrations and Anthropometric Measurements. The mean and standard deviations of the various anthropometric measurements of different age and sex groups are shown in table 1. There measurements have been compared with the Korean Standard. In the absence of local standards for arm circumference and skin-fold thickness over triceps, they have been compared with the standard from Jelliffe. Table 2,3, and 4 give anthropometric measurements and frequency (%) of anemia in children surveyed. The mean height of the children studid was 10 to 20 percent; below the Korean Standard. The distribution of height below 80 percent of the Standard was 21.2 percent, however, among anemic group this percentage was 27.7 percent. In general, the mean weight of the children was 10 to 15 percent below the Korean Standard. The percentage of children with weight less than 80 percent of the Standard was about 35 percent. But in the anemic group of the children, this percentage was 44 percent. The mean arm circumference was about 15 percent lower than the Jelliffe's standard. 61.2 percent of the children had values of arm circumference below 80 percent of the standard. Children with low hemoglobin levels, this percentage was 80 percent. The mean skinfold thickness over the triceps of the children studied was about 25 Percent lower than the Jelliffe's standard and 61.2 percent of the children had the value less than 80 percent of the standard. Among anemic children, this percentage was 70.8%. As may be seen from table 5, the mean hemoglobin concentration of the total group was 11.3g/100ml. Hemoglobin concentration was less than 11.0g/100ml. in 65(36.5%) of the 178 children. The degree of anemia in most of these children was mild with a hemoglobin level of less than 8.0g/100ml. found in only one child. In general, the prevalence of anemia was high in female children than male and decreased its frequency with increasing age. Relatively close relationship was observed between hemoglobin level and anthrophometric measurements especially high between arm circumference and skinfold thickness and hemoglobin but very low in height and low in weight and hemoglobin level, estimated by chi-square value. II. Serum iron, Transferrin saturation (1) Serum iron, and transferrin saturation Serum iron, transferrin saturation and red cell protoporphyrin concentrations were estimated in sub-sample of 84 children from 1 to 6 years and 24 older children between 7 and 13 years of age. The findings are presented in table 6. The mean serum iron concentration of the total group was 59ug/100ml. However, the level incrased with age from 36.6ug/100ml. (1-3years) to 80.8ug/100ml. (7-13 years). 60 percent of these children had a serum iron level less than 50ug/10ml. in the 1-3 years age group and 31.4 percent for 4-6 years group. These contrast with the finding of 12.5 percent anemic children in the 7-13 years age group. The mean transferrin saturation for the total group was 18.1 percent and frequency of anemia by transferrin saturation was observed same pattern as serum iron concentration. (2) Red cell protoporphyrin concentrations. (a) Red cell protoporphrin levels of children: Red cell protoporphyrin and other biochemical data are shown in table 4. The mean concentration in red cell of all children was fround 46.3ug/100ml. RBC. and differences with age groups were observed; in the age group 1-3 years, the mean concentration was $59.5{\pm}32.14$ ug/100ml. RBC; 4-6 years $44.1{\pm}22.57$ ug/100ml. RBC. and 7-13 years, $39.0{\pm}13.56$ ug/100ml. RBC. (b) Normal protoporphyrin values in adults: It was observed that in 10 normal adult males studied here the level of protoporphyrin in red cell ranged from 18 to 54 ug/100ml. RBC. and the mean concentration was $47.5{\sim}14.47$ ug/100ml. RBC. Other biochemical determination made on the same subjects are presented in table 8. (c) Red tell protoporphyrin concentration of occupational blood donors: The results of analyses for red cell protoporphyrin as well as serum iron, transferrin saturation and hemoglobin in the 76 blood donors are presented in table 7 and 8. In this experiment, donors were selected at random, however, most of them bled repeatedly because of poor economic situation, I doubt. Table 9 shows the distribution of red cell protoporphyrin concentration and hemoglobin concentration of occupational donors. The mean hemoglobin value for the total was 11.9 g/100 ml. When iron deficiency anemia is defined as a transferrin saturation below 15%, prevalence of anemia was 47.4 percent and the mean serum iron was 27.1ug/100ml. and red cell protoporphyrin, 168.3ug/100ml. RBC. However, mean serum iron and protoporphyrin concentration of above 15% transferrin saturation were 11.6 ug/100 ml. and 58.8 ug/100 ml. RBC. respectively. The mean Protoporphyrin concentration of non-anemic (above 15% transferrin saturation) donors was slightly higher than the results of normal adult males.

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