• Economic and Environmental Geology
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• v.48 no.2
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• pp.115-130
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• 2015

Extended elastic impedance (EEI) is an extension of elastic impedance (EI) which is a generalization of acoustic impedance (AI) for nonzero angles of incidence and can be tuned to be proportional to reservoir properties. In this study, we evaluated EEI inversion by estimating the P-($V_p$) and S-wave velocities ($V_s$), P-wave to S-wave velocity ratio ($V_p/V_s$), and Poisson's ratio of the Second Wall Creek Sand of the Teapot Dome field, Wyoming, USA. We also applied the EEI inversion technique to estimate porosity, gamma-ray values, and density of the Second Wall Creek Sand. Data used in the study include 3-D pre-stack seismic data from the southern part of the field and four wells, selected from a large well database. The $V_s$ logs at the wells were constructed from the $V_p$ logs using the empirical relationships. The percent prediction errors for the four velocity properties are less than about 5% except for Poisson's ratio at one well, supporting that the EEI inversion can be used in the prediction of rock properties. However, the results from the EEI inversion analysis of porosity, gamma-ray values, and density at the wells were unsatisfactory and thus these properties, which are not directly computed from velocities, may not be suitable for EEI inversion.

• Kyungpook Mathematical Journal
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• v.27 no.1
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• pp.27-33
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• 1987

Minimal s-Urysohn and minimal s-regular spaces are studied. An s-Urysohn (respectively, s-regular) space (X, $\mathfrak{T}$) is said to be minimal s-Urysohn (respectively, minimal s-regular) if for no topology $\mathfrak{T}^{\prime}$ on X which is strictly weaker than $\mathfrak{T}$, (X, $\mathfrak{T}^{\prime}$) is s-Urysohn (respectively s-regular). Several characterizations and other related properties of these classes of spaces have been obtained. The present paper is a study of minimal P-spaces where P refers to the property of being an s-Urysohn space or an s-regular space. A P-space (X, $\mathfrak{T}$) is said to be minimal P if for no topology $\mathfrak{T}^{\prime}$ on X such that $\mathfrak{T}^{\prime}$ is strictly weaker than $\mathfrak{T}$, (X, $\mathfrak{T}^{\prime}$) has the property P. A space X is said to be s-Urysohn [2] if for any two distinct points x and y of X there exist semi-open set U and V containing x and y respectively such that $clU{\bigcap}clV={\phi}$, where clU denotes the closure of U. A space X is said to be s-regular [6] if for any point x and a closed set F not containing x there exist disjoint semi-open sets U and V such that $x{\in}U$ and $F{\subseteq}V$. Throughout the paper the spaces are assumed to be Hausdorff.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.32 no.1
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• pp.1-9
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• 2022

Fixslicing AES is a technique that omits the Shiftrows step to minimize the cost of the linear layer of Bitsliced AES, showing a 30% performance over the Bitsliced technique. However, the amount of code increases to compensate for the omitted shiftrows. Therefore, it is proposed to be divided into Semi-Fixsliced in which only half of shiftrows are omitted and Fully-Fixsliced in which Shiftrows are omitted completely. In this paper, we propose a CTR mode implementation of Fixslicing AES on RISC-V using the pre-computed table technique. By utilizing the characteristics of the CTR mode, it is possible to perform fast encryption by omitting up to the second round SubBytes from the encryption process through pre-computed up to the second round SubBytes operation. Using this technique, it was confirmed that Semi-Fixsliced has a performance of 1,345 cycles per block and a performance improvement of 7% compared to the previous performance result, and Fully-Fixsliced has a performance of 1,283 cycles per block and a performance of 9% compared to the previous performance result on 32-bit RISC-V.

• Journal of Microbiology and Biotechnology
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• v.14 no.2
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• pp.330-336
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• 2004

Fifty-two pathogenic Vibrio parahaemolyticus strains were isolated from the environments of Busan and Yeosu, Korea. Forty-three of these strains showed protease activities, whereas 4 strains showed $\alpha / \beta$ hemolysin activities and 6 strains had urease activities. Their pathogenic factors were not overlapping except one strain, which had both protease and hemolysin activities. The 6 urease-positive strains (V. parahaemolyticus YKB4, YKB14, S25, YFB20, YFO21, and YFO22) showed the same biochemical characteristics as a reference strain [V. parahaemolyticus KCTC 2471 (urease-negative)], except for urease production. The 6 urease-positive strains showed different urease activities in their culture supernatant during the growth. The urease activity of S25 increased sharply at the late exponential phase, and was the highest at the initial stationary phase and was kept until the late stationary phase. The other 5 isolates, except C25, showed urease activities at the mid-stationary phase and increased steadily until the late stationary phase, when the urease activity was maximal. To compare the degree of virulence of V. parahaemolyticus with different pathogenic factors, hemolysin, protease, or urease-positive strains were injected into groups of 10 each of ICR mice (7- to l0-week-old males). The lethal rates of urease-positive V. parahaemolyticus, YKB14, YKB4, and S25, were significantly high, being 50, 70, and 80%, respectively. Protease-positive V. parahaemolyticus strains FM39 and FM50 showed 40% and 60% of lethal rate, respectively. Hemolysin-positive V. parahaemolyticus strains S34 and S72 had no mortality, similar to nonpathogenic V. parahaemolyticus FM12.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.8
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• pp.479-483
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• 2017

The effect of $NH_3$ plasma treatment on device characteristics was confirmed for an optimized thin film transistor of poly-Si formed by ELA. When C-V curve was checked for MIS (metal-insulator-silicon), Dit of $NH_3$ plasma treated and MIS was $2.7{\times}10^{10}cm^{-2}eV^{-1}$. Also in the TFT device case, it was decreased to the sub-threshold slope of 0.5 V/decade, 1.9 V of threshold voltage and improved in $26cm^2V^{-1}S^{-1}$ of mobility. Si-N and Si-H bonding reduced dangling bonding to each interface. When gate bias stress was applied, the threshold voltage's shift value of $NH_3$ plasma treated device was 0.58 V for 1,000s, 1.14 V for 3,600s, 1.12 V for 7,200s. As we observe from this quality, electrical stability was also improved and $NH_3$ plasma treatment was considered effective for passivation.

• Korean Journal of Ecology and Environment
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• v.45 no.1
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• pp.21-33
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• 2012

Survey on the phytoplankton community structure and distribution in the upstream watershed of the East River was carried out during the period from May, 2008 to April, 2009. A total composition of phytoplankton included 159 taxa, consisting of 7 orders, 56 genera, 139 species, and 40 unidenfied species. Among those, the diatoms and green algae were more frequently found during the investigation than the other taxa. Cocconeis placentula, Cymbella minuta, Diatoma vulgare, Melosira varians, Navicula cryptocephala, Scenedesmus acuminatus v. acuminatus, were among the most common. The standing crops of the phytoplankton ranged from 86 cells $mL^{-1}$ to 1,467 cells $mL^{-1}$. The dominant species were Achnanthes minutissima, Asterionella formosa, Aulacoseira ambigua, Cocconeis placentula, Coelastrum microporum, Cyclotella sp., Cymbella affinis, C. minuta, C. tumida, Diatoma vulgare, Fragilaria capucina, F. construens, F. crotonensis, Gomphonema affine, G. clevei, Melosira varians, Merismopedia elegans, Navicula cryptocephala, N. pupula, Nitzschia tryblionella, Oscillatoria anna, O. limosa, O. tenuis v. tenuis, Pediastrum duplex v. reticulatum, Phormidium tenue, Scenedesmus acuminatus v. acuminatus, S. acutus v. acutus, S. ecornis v. ecornis, S. quadricauda v. quadricauda, Spirogyra sp., Stigeoclonium sp., Synedra acus, S. ulna, and Ulothrix sp. The most dominant species was Cymbella minuta. The diversity index, evenness index, and dominance index ranged from 1.58 to 3.10, 051 to 0.95, and 0.22 to 0.74, respectively. The phytoplankton community structure of upstream stations of the survey area was influenced by the effluent of the Doam Lake.

• Korean Journal of Agricultural Science
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• v.28 no.2
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• pp.108-115
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• 2001

In this study, to propose the reasonable evaluation method of degree of consolidation considering the depth of soft ground, the two soft ground areas were chosen and analyzed for the consolidation degree. One was a western coast area in which depth of soft ground was low, and the other was a southern coast area in which depth of soft ground was deep. At the area in which depth of soft ground was low, Barron's and Yoshikuni's methods showed that the evaluation of consolidation degree was large, and it is reasonable that $C_h=C_v$ be recommended to apply the Hansbo's and the Onoue's methods. At the area in which depth of soft ground was deep, it is reasonable that $C_h=C_v$ be recommended to apply the Barron's and the Yoshikuni's methods, and $C_h=(2{\sim}3)C_v$ to apply the Hansbo's and the Onoue's methods. According to the Hansbo's and Onoue's methods, degree of consolidation proved to be applicable with measured data when using the $k_s=(1/3)k_v$ at the area which depth of soft ground was low and using the $k_s=(1{\sim}1/2)k_v$ at the area which depth of soft ground was deep. According to the Hansbo's and Onoue's methods, degree of consolidation was proved to be applicable with measured data when using ds=(3~5)dm at the area which depth of soft ground was low and using ds=2dm at the area which depth of soft ground was deep.

• Korean Journal of Community Nutrition
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• v.15 no.3
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• pp.329-341
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• 2010

The purpose of this study was to examine vegetable & fruit (V/F) intakes, beliefs and self-efficacy regarding V/F consumption, nutrition knowledge and eating behavior of elementary students. A survey was conducted to the 4th graders (n = 234) at two elementary schools in Guri, Kyunggi-do. About one-fourth of subjects were overweight or obese. Subjects had 4.2 servings of V/F a day, consuming 340.2 g of V/F. Girls consumed significantly more amounts of vegetables than boys (p < 0.05). Girls were more favorable regarding V/F consumption (p < 0.01), and believed more strongly on advantages of having V/F such as “good for skin” constipation prevention (p < 0.001) and cancer prevention (p < 0.05). Boys felt more strongly in disadvantages or barriers of eating V/F, including mother's cooking time constraints (p < 0.01), lack of past experience of eating V/F, and family members' disliking of V/F (p < 0.05). Girls felt more confident in eating V/F (p < 0.05) than boys; they also felt more confident in specific items of "eating fruits/salads instead of cookies/chips for snack" and "eating fruit juice/vegetable juice instead of soda"(p < 0.01). Subjects showed low level of nutrition knowledge, especially in items such as balanced meals, recommended servings of V/F and vitamin deficiency. Compared to boys, girls had more desirable eating behavior such as eating adequate amount of meals (p < 0.001), having a variety of foods, eating fruits daily, and having fatty foods less frequently (p < 0.05). Intakes of Ca and K were quite below the recommended level, while the intakes of protein, Na and vitamin A intake were much above the Dietary Reference Intakes (DRI) for 9-11 old children. Nutrient intakes expressed as %DRI was higher in girls for vitamin A (p < 0.01), energy and riboflavin (p < 0.05). High V/F consumption group (${\geq}5$ servings of V/F a day) compared to the counterparts showed higher self-efficacy and had better eating behaviors. Nutrition education for children should focus on increasing consumption of V/F, by helping them to increase self-efficacy for eating V/F and to recognize the benefits and reduce the barriers of eating V/F, especially in boys. It is also needed to provide nutrition information for balanced meals or increasing V/F consumption, and help the children to adopt desirable eating behavior.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.8
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• pp.54-61
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• 2001

A fully on-chip open-drain CMOS output driver was designed for high bandwidth DRAMs, such that its output voltage swing was insensitive to the variations of temperature and supply voltage. An auto refresh signal was used to update the contents of the current control register, which determined the transistors to be turned-on among the six binary-weighted transistors of an output driver. Because the auto refresh signal is available in DRAM chips, the output driver of this work does not require any external signals to update the current control register. During the time interval while the update is in progress, a negative feedback loop is formed to maintain the low level output voltage ($V_OL$) to be equal to the reference voltage ($V_{OL.ref}$) which is generated by a low-voltage bandgap reference circuit. Test results showed the successful operation at the data rate up to 1Gb/s. The worst-case variations of $V_{OL.ref}$ and $V_OL$ of the proposed output driver were measured to be 2.5% and 7.5% respectively within a temperature range of $20^{\circ}C$ to $90^{\circ}C$ and a supply voltage range of 2.25V to 2.75V, while the worst-case variation of $V_OL$ of the conventional output driver was measured to be 24% at the same temperature and supply voltage ranges.

• Journal of Embryo Transfer
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• v.13 no.3
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• pp.207-212
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• 1998

This study was conducted to determined if single subcutaneous (s.c.) injection of Folltropin-V dissolved in polyethyleneglycol (PEG) can replace as the standard multiple intramuscular (i.m.) injection. The results suggest that the s.c. treatment produced more corpora lutea, embryos recovered and transferable embryos as compared to the i.m. treatment (p<0.05). This study indicates that a single s.c. injection of Folltropin-V dissolved in PEG was effective for superovulatory response and embryo yield in Korean cattle.