• Natural Product Sciences
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• v.6 no.4
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• pp.189-192
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• 2000

A new isoflavone, $(+)-4'-O-methyl-8-C-{\beta}-D-glucopyranosylgenistein$, was isolated from the aerial parts of Spartidium saharae together with the known isoflavone, $(+)-8-C-{\beta}-D-glucopyranosylgenistein$ as well as dipiperidine alkaloids, (+)-ammodendrine and (+)-N-acetyl hystrine. Details of their structure elucidation are based on chemical and spectroscopic methods. N-formyl ammodendrine was detected by GC-MS. The potential chemotaxonomic value of the alkaloid content is explored. Cytotoxic activity has been determined for both alcoholic extract and isolated compounds.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.1
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• pp.119-124
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• 1994

Experiments were performed to determine age-associated changes in ornithine decarboxylase (ODC) gene and Ha-ras cellular oncogene expression in tissues of female rats. In the kidney, ODC mRNA levels did not show age-associated changes, while ODC enzyme activities were decreased with advancing age from 3 to 10 months. These results suggest that post-transcriptional mechanism (s) are involved in the age-dependent decrease in renal ODC enzyme activity. In addition, we found no correlation between testosterone-induced renal ODC expression and DNA methylation pattern. Ha-ras mRNA levels in brain decreased as animals aged from 3 to 6 months, while renal Ha-ras mRNA levels were not influenced by age. Results demonstrate the age-dependent expression of Ha-ras in a tissue-specific manner.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.876-881
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• 2003

Reliable attitude estimation during the launch and early orbit phase is a critical issue for a satellite. Typically gyroscopes and other sensors are utilized to estimate the attitude during this phase. It is difficult to estimate the attitude quickly and reliably using gyroscopes because it requires a large computational load and accurate sensor measurements. Furthermore, the gyroscope failure may lead to the loss of the satellite. This paper suggests a simple attitude estimation method of a low earth orbit satellite without using gyroscopes, but only using sun sensors and magnetometers in the sun-acquisition mode. Using Kompsat-I telemetry data, we verified that the suggested algorithm provides attitude estimation within 3 degrees on each axis.

• International Journal of Control, Automation, and Systems
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• v.6 no.5
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• pp.627-638
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• 2008

With the shift of the electric power industry from a regulated monopoly structure to a competitive market environment, the focus of the transmission expansion planning has been moving from reliability-driven transmission expansion to market-based transmission expansion. In market-based transmission expansion, however, a growing demand for electricity, an increasing number of transmission bottlenecks, and the falling levels of transmission investment have created the need for an incentive to motivate investors. The expectation of profit serves as a motivational factor for market participants to invest in transmission expansion in a competitive market. To promote investment in transmission expansion, there is an increasing need for a systematic method to examine transmission expansion for investment incentives from multiple perspectives. In this paper, the transmission expansion problem in a competitive market environment is formulated from ISO and investors' perspectives. The proposed method uses parametric analysis to analyze benefits for investors to identify the most profitable location and amount for transmission addition. Numerical results are presented to demonstrate the effectiveness of the proposed method.

• The Plant Pathology Journal
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• v.33 no.2
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• pp.109-117
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• 2017

Tan spot caused by the fungus Pyrenophora triticir-repentis is a serious disease of wheat, which is on increase in recent years in Mediterranean region. In the field this fungus produces a diamond-shaped necrotic lesions with a yellow halo on wheat foliage. The objective of this study was to characterize and compare several monospore isolates of P. tritici-repentis collected from different infected wheat fields in various locations of Algeria, and find the morphological differences between them, if any. The results revealed wide morphologically variation among the isolates based on colony colors and texture, mycelial radial growth and conidial size.

• Journal of the Korean Institute of Navigation
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• v.1 no.1
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• pp.1-16
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• 1977

The aspects of Omega phase prediction are briefly reviewed, and Swanson's Model and Pierce's Model are presented. The equations for the Omega phase prediction and the most probable coefficients of the propagating equations are derived on the base of Pierce's Model by the least square method. The coefficients are calculated from the data which are the phase differences between the pairs of the Station A (Aldra, Norway), C(Haiku, Hawaii), and D(La Mour, North Dakota) observed at Busan Harbor of the South Coast of Korea in June and September, 1976. It is clearly shown that the standard deviations of the observed lane values at Busan Harbor are as followed: 1. June, 1976. Pair (A-C) : 0.1446 Pair (C-D) : 0.2598 2.September, 1976. Pair (A-D) : 0.3958 Pafr (C-D) : 0.3278 As a conclusion of the above investigation, it is shown that the Omega phase velocity can be predicted by the method, proposed in this paper, of analyzing the diurnal and seasonal variations of the Omege phase velocity except SID, PCD and AZD. If more observed data are employed, more exact Omega phase velocity is expected to be obtained.

• Wind and Structures
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• v.11 no.4
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• pp.291-302
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• 2008

Three-dimensional engineering simulations of momentum-driven tornado-like vortices are conducted to investigate the flow dynamics dependency on swirl ratio and the possible relation with real tornado Fujita scales. Numerical results are benchmarked against the laboratory experimental results of Baker (1981) for a fixed swirl ratio: S = 0.28. The simulations are then extended for higher swirl ratios up to S = 2 and the variation of the velocity and pressure flow fields are observed. The flow evolves from the formation of a laminar vortex at low swirl ratio to turbulent vortex breakdown, followed by the vortex touch down at higher swirls. The high swirl ratios results are further matched with full scale data from the Spencer, South Dakota F4 tornado of May 30, 1998 (Sarkar, et al. 2005) and approximate velocity and length scales are determined.

• Asian Journal of Business Environment
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• v.2 no.2
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• pp.5-11
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• 2012

Purpose - This research examined the relationship between business orientation and business goals and satisfaction of Korean-American business owners. Research design/data/methodology - Entrepreneurial Orientation (EO) and Small Business Orientation (SBO) were the theoretical constructs underlying this research. The responses from 200 Korean-American business owners who participated in the 2005 National Minority Business Owner Surveys were used for data analysis. Results - Noneconomic business goal was positively related to business owners' SBO tendency, and those with a SBO tendency had the higher business satisfaction than those with EO. Conclusions - The findings suggest that policy makers should develop business assistance programs that correspond with owners' business orientation.

• Asia-Pacific Journal of Business
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• v.3 no.1
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• pp.1-9
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• 2012

The Index of Learning Styles (ILS) instrument based on the Felder-Silverman Learning Style Model was used to determine distribution of learning styles of 125 South Korean business students enrolled in a South Korean institution of higher education. Results show that greater proportion of South Korean business students surveyed in this study prefer sensing over intuitive, visual over verbal, reflective over active, and global over sequential learning styles. The majority of business students have a balanced learning style in all four dimensions of the Felder-Silverman model. Among the students that do not have a balanced learning style, students with sensing, visual, reflective, and global learning styles dominate. Gender difference in learning style preference was not statistically significant for any of the four dimensions.

• International Journal of Concrete Structures and Materials
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• v.5 no.1
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• pp.43-48
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• 2011

This paper presents the performance of anchor systems for reinforced concrete beams retrofitted with carbon fiber reinforced polymer (CFRP) strips. Nine simply-supported beams are tested with various anchor systems such as steel hooks, steel plates with anchor bolts, CFRP anchor plates, and near-surface mounted (NSM) CFRP strip. The effects of these anchors on the behavior of the retrofitted beams are discussed, including load-carrying capacity, failure modes, and ductility characteristics. Test results indicate that end-anchorage is an important parameter when a CFRP-retrofit design is conducted. Mechanical bolts and NSM CRFP anchors are recommended.