• Title/Summary/Keyword: Positive Temperature Coefficient

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Characterization of Seasonal and Annual Variations in Quality of Rice Brands Distributed in Jeonnam Province (전남 유통 브랜드쌀 품질의 연중 및 연차 변이 특성)

  • An, Kyu Nam;Lee, In;Shin, Seo Ho;Min, Hyun Kyoung;Kwon, Oh Do;Park, Heung Gyu;Shin, Hae Ryong;Kim, Han Yong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.62 no.2
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    • pp.79-86
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    • 2017
  • This study was conducted to analyze seasonal and annual variations in rice quality and factors affecting the quality, for quality evaluation of the brand rice varieties produced in Jeonnam region. Coefficient of variation (CV) values for the seasonal variation in the rice quality were 3.1% in Toyo value, 2.1% in whiteness, 1.6% in protein content, 1.0% in moisture content, and 0.4% in head rice ratio. Quality characteristics of the brand rice varieties generally showed a decreasing tendency after April, as the months progressed. CV values for the annual variation in the rice quality were relatively high at 5.6% in protein content and 5.2% in Toyo value whereas those for whiteness and head rice ratio were relatively low, at 2.7% and 1.8%, respectively. Palatability and protein content showed high correlations with minimum air temperature, sunshine hours, rainfall, and daily temperature range. Head rice ratio had a negative correlation with daily temperature range whereas chalky rice ratio had a positive correlation with rainfall. Based on these results, we formulated a multiple regression equation to estimate palatability of cooked rice using protein content, whiteness, head rice ratio, and moisture content as follows: y = - 6.71a + 2.27b + 1.29c + 0.51d - 15.34 ($R^2$=0.51*) (y: palatability of cooked rice, a: protein content, b: moisture content, c: whiteness, d: head rice ratio).

Partial Characterization of Physicochemical and Kinetic Properties of $Ca^{++}-ATPase$ System in Luteal Membranes (황체막에서의 $Ca^{++}-ATPase$의 특성)

  • Choi, Gyu-Bog;Koo, Bon-Sook;Kim, In-Kyo
    • The Korean Journal of Physiology
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    • v.20 no.2
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    • pp.257-270
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    • 1986
  • It has been reported that the luteal function may be regulated by the intracellular calcium in luteal cells (Higuchi et al, 1976; Dorflinger et at, 1984; Gore and Behrman, 1984) which is adjusted partially by $Ca^{++}-ATPase$ activities in luteal cell membranes (Verma and Pennistion, 1981). However, the physicochemical and kinetic properties of $Ca^{++}-ATPase$ in luteal membranes were not fully characterized. This study was, therefore, undertaken to partially characterize the physicochemical and kinetic properties of $Ca^{++}-ATPase$ system in luteal membranes and microsomal fractions, known as an one of the major $Ca^{++}$ storge sites (Moore and Pastan, 1978), from the highly luteinized ovary Highly luteinized ovaries were obtained from PMSG-hCG injected immautre female rats. Light membrane and heavy membrane fractions and microsomal fractions were prepared by the differential and discontinuous sucrose density gradient centrifugation method desribed by Bramley and Ryan (1980). Light membrane and heavy membrane fractions and microsomal fractions from highly luteinized ovaries are composed of the two different kinds of $Ca^{++}-ATPase$ system. One is the high affinity $Ca^{++}-ATPase$ which is activated in low $Ca^{++}$ concentration (Km, 10-30 nM), the other is low affinity $Ca^{++}-ATPase$ activated in higher $Ca^{++}$ concentration $(K_{1/2},\;40\;{\mu}M)$. At certain $Ca^{++}$ concentrations, activities of high and low affinity $Ca^{++}-ATPase$ are the highest in light membrane fractions and are the lowest in microsomal fractions. It appeares that high affinity $Ca^{++}-ATPase$ system have 2 binding sites for ATP (Hill's coefficient; around 2 in all membrane fractions measured) and the positive cooperativity of ATP bindings obviously existed in each membrane fractions. The optimum pH for high affinity $Ca^{++}-ATPase$ activation is around S in all membrane fractions measured. The lipid phase transition temperature measured by Arrhenius plots of high affinity $Ca^{++}-ATPase$ activity is around $25^{\circ}C$. The activation energies of high affinity $Ca^{++}-ATPase$ below the transition temperature are similar in each membrane fractions, but at the above transition temperature, it is the hightest in heavy membrane fractions and the lowest in microsomal fractions. According to the above results, it is suggested that intracellular $Ca^{++}$ level, which may regulate the luteal function, may be adjusted primarily by the high affinity $Ca^{++}-ATPase$ system activated in intracellular $Ca^{++}$ concentration range $(below\;0.1\;{\mu}M)$.

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Spatio-temporal distributions of the newly described mixotrophic dinoflagellate Yihiella yeosuensis (Suessiaceae) in Korean coastal waters and its grazing impact on prey populations

  • Jang, Se Hyeon;Jeong, Hae Jin
    • ALGAE
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    • v.35 no.1
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    • pp.45-59
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    • 2020
  • To investigate the spatio-temporal distributions of the mixotrophic dinoflagellate Yihiella yeosuensis in Korean coastal waters and its grazing impact on prey populations, water samples were seasonally collected from 28 stations in the East, West, and South Seas of Korea and Jeju Island from April 2015 to October 2018. The abundances of Y. yeosuensis in the water samples were quantified using quantitative real-time polymerase chain reaction (qPCR). Simultaneously, the physical and chemical properties of water from all sampled stations were determined, and the abundances of the optimal prey species of Y. yeosuensis, the prasinophyte Pyramimonas sp. and the cryptophyte Teleaulax amphioxeia, were quantified using qPCR. Y. yeosuensis has a wide distribution, as is reflected by the detection of Y. yeosuensis cells at 23 sampling stations; however, this distribution has a strong seasonality, which is indicated by its detection at 22 stations in summer but only one station in winter. The abundance of Y. yeosuensis was significantly and positively correlated with those of Pyramimonas sp. and T. amphioxeia, as well as with water temperature. The highest abundance of Y. yeosuensis was 48.5 cells mL-1 in Buan in July 2017, when the abundances of Pyramimonas sp. and T. amphioxeia were 917.6 and 210.4 cells mL-1, respectively. The growth rate of Y. yeosuensis on Pyramimonas sp., calculated by interpolating the growth rates at the same abundance, was 0.49 d-1, which is 37% of the maximum growth rate of Y. yeosuensis on Pyramimonas sp. obtained in the laboratory. Therefore, the field abundance of Pyramimonas sp. obtained in the present study can support a moderate positive growth of Y. yeosuensis. The maximum grazing coefficient for Y. yeosuensis on the co-occurring Pyramimonas sp. was 0.42 d-1, indicating that 35% of the Pyramimonas sp. population were consumed in 1 d. Therefore, the spatio-temporal distribution of Y. yeosuensis in Korean coastal waters may be affected by those of the optimal prey species and water temperature. Moreover, Y. yeosuensis may potentially have considerable grazing impacts on populations of Pyramimonas sp.

Microstructure and Characterization of Ni-C Films Fabricated by Dual-Source Deposition System

  • Han, Chang-Suk;Kim, Sang-Wook
    • Korean Journal of Materials Research
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    • v.26 no.6
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    • pp.293-297
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    • 2016
  • Ni-C composite films were prepared by co-deposition using a combined technique of plasma CVD and ion beam sputtering deposition. Depending on the deposition conditions, Ni-C thin films manifested three kinds of microstructure: (1) nanocrystallites of non-equilibrium carbide of nickel, (2) amorphous Ni-C film, and (3) granular Ni-C film. The electrical resistivity was also found to vary from about $10^2{\mu}{\Omega}cm$ for the carbide films to about $10^4{\mu}{\Omega}cm$ for the amorphous Ni-C films. The Ni-C films deposited at ambient temperatures showed very low TCR values compared with that of metallic nickel film, and all the films showed ohmic characterization, even those in the amorphous state with very high resistivity. The TCR value decreased slightly with increasing of the flow rate of $CH_4$. For the films deposited at $200^{\circ}C$, TCR decreased with increasing $CH_4$ flow rate; especially, it changed sign from positive to negative at a $CH_4$ flow rate of 0.35 sccm. By increasing the $CH_4$ flow rate, the amorphous component in the film increased; thus, the portion of $Ni_3C$ grains separated from each other became larger, and the contribution to electrical conductivity due to thermally activated tunneling became dominant. This also accounts for the sign change of TCR when the filme was deposited at higher flow rate of $CH_4$. The microstructures of the Ni-C films deposited in these ways range from amorphous Ni-C alloy to granular structures with $Ni_3C$ nanocrystallites. These films are characterized by high resistivity and low TCR values; the electrical properties can be adjusted over a wide range by controlling the microstructures and compositions of the films.

Comparison of Real Time Water Soluble Organic Carbon Measurements by Two PILS-TOC Analyzers (PILS-TOC를 이용한 실시간 대기 중 수용성 유기탄소 비교 측정)

  • Park, Da-Jeong;Kang, Seokwon;Lee, Taehyoung;Shin, Hye-Jung;Shon, Zang-Ho;Bae, Min-Suk
    • Journal of Korean Society for Atmospheric Environment
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    • v.32 no.6
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    • pp.633-641
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    • 2016
  • Two identical Particle Into Liquid Samplers-Total Organic Carbon (PILS-TOC) were operated to measure fine particle Water Soluble Organic Carbon (WSOC) for one week on Feb. in 2016. The dual instrument operations provided validated WSOC concentrations to have a continuous WSOC measurement during the sample analysis period. Both PILS-TOC instruments were operated downstream of an carbon denuder to remove positive adsorption artifacts associated with semi-volatile organic compounds. Comparison of WSOC showed good agreement each other. The linear regression had a coefficient of determination ($r^2$) of 0.92 and a regression slope of 1.01 for the first period. The lower collection efficiency due to lower steam temperature is discussed. In addition, the potential primary source related to WSOC based on the comparison of black carbon (BC) concentrations is explained. The results of good agreement between two PILS-TOC measurements can provide the validation of WSOC cooperations and knowledge regarding the origins of WSOC and their behaviors.

Millimeter-wave Dielectric Ceramics of Alumina and Forsterite with High Quality factor and Low Dielectric Constant

  • Ohasto, Hitoshi;Tsunooka, Tsutomu;Ando, Minato;Ohishi, Yoshihiro;Miyauchi, Yasuharu;Kakimoto, Ken ichi
    • Journal of the Korean Ceramic Society
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    • v.40 no.4
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    • pp.350-353
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    • 2003
  • Millimeter-wave dielectric ceramics have been used like applications for ultrahigh speed wireless LAN because it reduces the resources of electromagnetic wave, and Intelligent Transport System (ITS) because of straight propagation wave. For millimeterwave, the dielectric ceramics with high quality factor (Q$.$f), low dielectric constant($\varepsilon$), and nearly zero temperature coefficient of resonant frequency ($\tau$) are needed. No microwave dielectric ceramics with these three properties exist except Ba(Mg$\_$1/3/Ta/sub1/3/)O$_3$ (BMT), which has a little high s: In this paper, alumina (Al$_2$O$_3$) and fosterite (Mg$_2$SiO$_4$), candidates for millimeter-wave applications, were studied with an objective to get high q$.$f and nearly zero $\tau$$\_$f/ For alumina ceramics, q$.$f more than 680,000 GHz was obtained but it was difficult to obtain nearly zero Qf. On the other hand, for forsterite ceramics, q$.$f was achieved from 10,000 GHz of commercial for sterite to 240,000 GHz of highly purified MgO and SiO$_2$ raw materials, and $\tau$$\_$f/ was reduced a few by adding TiO$_2$ with high positive $\tau$$\_$f/.

Characterization and Comparison of Doping Concentration in Field Ring Area for Commercial Vertical MOSFET on 8" Si Wafer (8인치 Si Power MOSFET Field Ring 영역의 도핑농도 변화에 따른 전기적 특성 비교에 관한 연구)

  • Kim, Gwon Je;Kang, Ye Hwan;Kwon, Young-Soo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.26 no.4
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    • pp.271-274
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    • 2013
  • Power Metal Oxide Semiconductor Field Effect Transistor's (MOSFETs) are well known for superior switching speed, and they require very little gate drive power because of the insulated gate. In these respects, power MOSFETs approach the characteristics of an "ideal switch". The main drawback is on-resistance RDS(on) and its strong positive temperature coefficient. While this process has been driven by market place competition with operating parameters determined by products, manufacturing technology innovations that have not necessarily followed such a consistent path have enabled it. This treatise briefly examines metal oxide semiconductor (MOS) device characteristics and elucidates important future issues which semiconductor technologists face as they attempt to continue the rate of progress to the identified terminus of the technology shrink path in about 2020. We could find at the electrical property as variation p base dose. Ultimately, its ON state voltage drop was enhanced also shrink chip size. To obtain an optimized parameter and design, we have simulated over 500 V Field ring using 8 Field rings. Field ring width was $3{\mu}m$ and P base dose was $1e15cm^2$. Also the numerical multiple $2.52cm^2$ was obtained which indicates the doping limit of the original device. We have simulated diffusion condition was split from $1,150^{\circ}C$ to $1,200^{\circ}C$. And then $1,150^{\circ}C$ diffusion time was best condition for break down voltage.

Effect of Antenatal Education on Pregnant Women (임부들을 대상으로 한 산전교육의 효과)

  • Park, Choon-Hwa;Lee, Chae-Un
    • Women's Health Nursing
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    • v.8 no.1
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    • pp.34-54
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    • 2002
  • This study was conducted to assess the knowledge and educational need of pregnant women relating to antepartum, delivery, puerperium period and to identify the variables which influenced their knowledge and educational need. The study subjects were 77 antepartum women who had antenatal educations and 106 antepartum women who did not have antenatal education. Number of total antepartum women were 183. Data were collected from women who visited for antenatal care at general hospitals and public health centers in Pusan and Kyungnam area using qestionnaires from Feb. 1. 1998 to Apr. 20. 1998. SAS/PC program was used for data analysis. ; Chi-square test, t-test, Pearson's Correlation Coefficient, ANOVA(Duncan procedure) and MANOVA. The results of this study were as follows: 1. Relating to the antepartum period between two groups, the knowledge about the number of antenatal care was low, relating to labor the knowledge about the time fix the fetal position and relating to postpartum, the knowledge about the change of blood pressure and body temperature was low. 2. The comparision means of knowledge were adjusted by social demographic characteristics related to knowledge. There were statistically significant differences in total mean score of knowledge about pregnancy, delivery and postpartum between two groups. In full marks 19, the mean scores of the educational group and non-educational group were 13.08 and 11.74 respectively (P=.000). In resultly, there are statistically significant differences between two groups. The effectiveness of antenatal education group was very high and showed its importance. 3. The comparision means of educational need were adjusted by social demographic characteristics related to educational need. The mean scores of educational need were statistically significantly different in pregnancy, delivery and puerperium period. 4. There were positive correlations between the knowledge and educational level, duration of marriage and total numbers of pregnancy. There were negative correlation between the educational need and age, educational level, duration of marriage and total number of pregnancy. The above results showed the effects of antenatal education.

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Development of High Density Inductively Coupled Plasma Sources for SiH4/O2/Ar Discharge (고밀도 유도 결합 플라즈마 장치의 SiH4/O2/Ar 방전에 대한 공간 평균 시뮬레이터 개발)

  • Bae, S.H.;Kwon, D.C.;Yoon, N.S.
    • Journal of the Korean Vacuum Society
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    • v.17 no.5
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    • pp.426-434
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    • 2008
  • A space averaged $SiH_4/O_2/Ar$ simulator for the high density inductively coupled plasma sources for $SiH_4/O_2/Ar$ discharge is developed. The developed simulator uses space averaged fluid equations for electrons, positive ions, negative ions, neutral species, and radicals in $SiH_4/O_2/Ar$ plasma discharge, and the electron heating model including the anomalous skin effect. Using the developed simulator, the dependency of the density of charged particles, neutral particles, and radicals, the electron temperature, the plasma resistance, and the power absorption coefficient for the RF power and pressure is calculated.

An Exploratory Study of Electrochemical Skin Conductance for the Deficiency Pattern Identification in Diabetic Patients (당뇨병 환자의 허증별 전기전도도 특성에 대한 탐색적 관찰 연구)

  • Kim, Kahye;Kim, Jihye;Kim, Jaeuk U.
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.22 no.1
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    • pp.57-67
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    • 2018
  • Objectives The objective of this study is to examine the interpretability of the questionnaire-based pattern identification in terms of biosignals. For this purpose, we investigate the relationship between electrochemical skin conductance (ESC) and Qi-Blood-Yin-Yang Deficiency Questionnaire (QBYY-Q) in diabetic patients. Methods A total of 40 patients with diabetes mellitus answered the QBYY-Q and their ESC were measured by SUDOSCAN device (a diabetes screening device, France). To analyze the relationship between QBYY-Q and ESC, ANOVA analysis and Scheffe test were performed and Pearson correlation coefficients were obtained. Results Of the 40 diabetic patients, 23 (57.5%) were males and 17 (42.5%) were females. According to the QBYY-Q, 9 patients were classified into Qi deficiency pattern (QD), 9 patients were Blood deficiency pattern (BD), 10 patients were Yin deficiency pattern (YiD) and 12 patients were Yang deficiency pattern (YaD). Demographic information (age, body mass index, duration of illness, etc.), signs of vitality (blood pressure, body temperature, etc.), fasting plasma glucose and glycated hemoglobin were not significantly different in each deficiency pattern. The ESC of the right leg was significantly lower in the BD group compared to the YiD group (p<0.022). Pearson's correlation coefficient was negatively correlated with the BD questionnaire score (r=-0.343, p <0.05). Finally, ESC showed a positive correlation with hemoglobin and erythrocyte levels in all limbs (r=0.483, p<0.01). Conclusions We showed that ESC could be used to classify the Deficiency pattern identifications in diabetic patients. Especially, the ESC was significantly lower in the BD group and was negatively correlated with the BD scores. It implies the potential utility of the ESC to understand the BD in terms of modern biosignals.

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