• Management Science and Financial Engineering
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• v.5 no.2
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• pp.55-59
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• 1999

In this note, we introduce the Fire Sequencing Problem, which arises in military operations. Given m weapons, n fixed targets nad required duration of firing of the weapons on the targets, we want to determine the start time of firing on each target so that makespan is miniized while satisfying various operational constraints. We show that the decision problem of the Fire Sequencing problem is strongly NP-complete and remains strongly NP-complete even if the number of weapons is two. We also briefly discuss the results with respect to the complexities of several well-known scheduling models.

• Journal of Korean Neurosurgical Society
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• v.29 no.9
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• pp.1267-1270
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• 2000

Krukenberg tumor has been traditionally defined as gastrointestinal malignancy metastatic to the ovary, and is known to account for 1 to 3% of ovarian neoplasms. The nature and behavior of this particularly virulent tumor still remains unclear. We have experienced a case of Krukenberg tumor with brain metastasis. A clinical description of our case is presented with a review of the literature.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.11
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• pp.955-962
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• 2000

Although large space structures(LSS) such as a space station, a solar power station satellite, etc., are theoretically distributed parameter and infinite-dimensional systems, they have to be modeled into a lumped parameter and large finite-dimensional system for control system design. Besides, there remains the fundamental problem that the modeled large finite-dimensional system must be controled with a much smaller dimensional controller due to the limitation of computing resources. This causes the spillover phenomenon which degrades control performances and reduces the stability margin. Furthermore, it may destabilize the entire feedback control system. In this paper, we propose a novel spillover suppression method in the active vibration control of large flexible structures by using eigenstructure assignment. Its validity and effectiveness are investigated and verified by the numerical experiments using a simply supported flexible beam, which is modeled to have four controlled modes and eight uncontrolled modes.

• BMB Reports
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• v.47 no.4
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• pp.227-232
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• 2014

Histone deacetylase-3 (HDAC3) is involved in cellular proliferation, apoptosis and transcriptional repression. However, the role of HDAC3 in angiogenesis remains unknown. HDAC3 negatively regulated the expression of angiogenic factors, such as VEGF and plasminogen activator inhibitor-1 (PAI-1). HDAC3 showed binding to promoter sequences of PAI-1. HDAC3 activity was necessary for the expression regulation of PAI-1 by HDAC3. VEGF decreased the expression of HDAC3, and the down-regulation of HDAC3 enhanced endothelial cell tube formation. HDAC3 negatively regulated tumor-induced angiogenic potential. We show the novel role of HDAC3 as a negative regulator of angiogenesis.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.5
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• pp.663-669
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• 2008

A rapid growth of automobile industry has become a major cause for the environmental pollution of big cities, which has driven the emission regulation into extreme. The study of alternative fuel is one of the many researches for improving car emissions. In this study, the effect of an ethanol mixing rate on the engine performance of exhaust emissions, fuel consumption and a maximum torque is assessed for a gasoline engine without any retrofit. The result shows that maximum torque is not reduced in the range of ethanol mixing rate of 10 to 15%. CO and NOx is reduced with the increase of ethanol mixing rate and the fuel consumption remains in similar level.

• Journal of Ecology and Environment
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• v.38 no.1
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• pp.113-118
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• 2015

Conservation drones are remote-controlled devices capable of collecting information from difficult-to-access places while minimizing disturbance. Although drones are increasingly used in many research disciplines, their application to wildlife research remains to be explored in depth. This paper reports on the use of Phantom 2 Vision+ for monitoring areas in two national parks in South Korea. The first research area was conducted in Chiaksan National Park, and the second in Taeanhaean National Park. The aim of this research is to introduce ecologists and researchers alike to conservation drones and to show how these new tools have are fundamentally helping in the development of natural sciences. We also obtained photographs and videos of monitoring areas within our test site.

• Korean Journal of Pharmacognosy
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• v.28 no.1
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• pp.42-47
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• 1997

The prescription of Gal Gun Tang, which has been used for treatment of cold, fever, and muscular pain in Chinese herb medicine, is produced in the form of decoction However, the storage problem for this dosage form remains unsettled. Using HPLC and GC, we examined quantitative change of major constituents caused by time-progress and temperature-change. Nine major constituents, such as cinnamaldehyde, cinnamic acid, ephedrine, puerarin, paeoniflorin, daidzin, benzoic acid, glycyrrhizin and liquiritin, were selected as references. The content of cinnamaldehyde significantle decreased by the increase of temperature. While that of cinnamic acid increased. Benzoic acid showed the most significant change of the content in three months at $40^{\circ}C$. It is suggested that most of constituents are considerably stable when kept frozen.

• Bulletin of the Korean Space Science Society
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• 2009.10a
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• pp.37.1-37.1
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• 2009

Solar type II radio burst is regarded as a signature of coronal shock. However its association with coronal mass ejections (CMEs)-driven shock and/or flare blast waves remains controversial. On December 31 2007, SOHO/LASCO and STEREO/COR observed a CME that occurred on the east limb of the Sun. Meanwhile, two type II bursts were observed sequently by KASI/E-Callisto and the Culgoora radio observatory during the CME apparence time. In this study, we estimate kinematics of the two coronal shocks from dynamic spectrum of the multiple type II bursts and compare with the kinematics of the CME derived from the space observations. An origin of the multiple type II bursts is inspected and discussed briefly.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.852-857
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• 2004

In this paper, an angular self-sensing algorithm is proposed and implemented to a Lorentz force type integrated motor-bearing system. It is based on the principle that the flux linkages of stator windings, calculated from the voltage and torque control current, are the functions of the rotor angle. The tracking angular position error is proven to vanish using the Lyapunov stability method, and the experimental results show that the initial error decays within about 5 seconds. It is found that the resolution of the algorithm remains about 1º over the speed range of 100 to 1000 rpm.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.5
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• pp.392-399
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• 2008

Accurate measurement of speed and altitude of flying vehicles in air data system remains a critical technical issue. A highly reliable Pitot-static probe is required to obtain air data such as total pressure and static pressure. In this study, an analysis of the characteristics of flowfield around the Pitot-static probe was performed by using a Navier-Stokes CFD code. In addition, for the purpose of finding an optimal configuration, a technique based on the response surface method is applied to the problem with design parameters including shape of the nose section and cone angle. It is shown that the optimal configuration fulfills the MIL specification in wider range of high angles of attack.