• Proceedings of the KIEE Conference
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• 2001.11a
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• pp.251-254
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• 2001

Internal and external forces may be applied on the power cable in the both process of transportation and installation. Even though the EHV power cables have the structure of metal sheath and plastic jacket etc. to minimize these negative influences, the unusual forces result in the unexpected deformation of the cable. Compressing moulded XLPE model cable sheets were prepared and locally dented with round-edge and square-edge tools. All data were analyzed employing Weibull distribution. The breakdown strength of dented molded specimens showed lower values than the normal ones by 10-60%.

• Journal of electromagnetic engineering and science
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• v.17 no.3
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• pp.120-125
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• 2017

A satellite communication (Satcom) antenna mounted on a moving platform provides a controlled heading that enables a geosynchronous satellite to communicate with the ground. A monopulse tracking method is effective for antenna control on a vehicle when it vibrates severely. However, this method has unexpected obstacles and its control performance is insufficient. To improve its control performance, the control command and monopulse error, the signal delay, and the radome effect are evaluated through tests. The authors then propose a method to transform the antenna error from 3D coordinates to 2D antenna coordinates. As a result, the antenna control performance is improved. As indicated in this study, examining antenna systems using the monopulse method on moving platforms is possible by understanding the antenna test process.

• Bulletin of the Korean Chemical Society
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• v.30 no.9
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• pp.2017-2020
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• 2009

Three complexes, [bis(L-, D- and DL-alaninato)(diaqua)]nickel(II) di-hydrate, were prepared and characterized by X-ray crystallography, gas chromatography, UV-Visible spectroscopy and isothermal calorimetry. Small deviations from the 50:50 distribution of the enantiomers assigned to chiral preferences of the ligands in the complexes were observed. The surprising and unexpected results indicate that complexing alanine with nickel(II) ion alters the racemization rates of D and L isomers of the amino acid. The precipitated complex due to change in pH resulted in preferential precipitation of one isomer with respect to the other. It has been observed that this alternation is ogmented by the long time span which would result in preferential protein forming from the L-isomer. Although the results are bizarre and perplexing, they are fascinating and sound scientifically.

• Journal of the Korean Chemical Society
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• v.44 no.1
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• pp.30-36
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• 2000

Upon Pd(0)-catalyzed coupling reaction of (2R)-2-(N,N-ditosylimido)-3-butenyl methyl malonate (4) which was selected for the total synthesis of A-factor, (3R)-2-(6-methylheptanoyl)-3-hydroxy methyl-4-buttinolide (1), an unexpected 14-membered cyclic compound, bis(2-methoxycabonyl-(4E)-hexenolide) (15) was obtained. The structure of this compound was conformed by X-ray crystallography. This result implies that this method can be applied the synthesis of various size of symmetrical macrocyclic compounds.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.314-317
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• 2002

The sloshing phenomenon sometimes happens to be occurred in the liquid storage tank due to the unexpected and/or inevitable vibrating conditions and may result in severe effects on the structural stability. This study deals with the development of experimental techniques for the evaluation of sloshing behavior in the liquid storage tank and for the identification of natural frequencies and mode shapes by varying with various vibrating conditions. In addition, suitable method is suggested to minimize the sloshing effect on the liquid storage tank and its validity is experimentally investigate d.

• Journal of Trauma and Injury
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• v.31 no.1
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• pp.29-33
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• 2018

Traumatic blunt aortic injury especially on proximal ascending aorta is a rare injury with a few reports. Generally emergency surgical management was performed. In this case, however, in multiple trauma with brain injury, emergency surgical management of aortic injury might result in unexpected secondary injury of the brain. Herein, we report a case of a 33-year-old man who was driving a truck was injured in a head-on collision. Evaluation revealed a pseudoaneurysm on his ascending aorta concomitant with epidural hemorrhage. He was treated by surgical management of his ascending aorta after 3 days from accident. There were no postoperative and neurologic complications and the patient was discharged after 18 days.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.5
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• pp.805-811
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• 2011

Aircraft MLG and wing structures have been recognized as fatigue critical structures and exposed to the risk of fatigue crack initiation and propagation. Furthermore, these structures are frequently subjected to serious dynamic loading condition during a Hard Landing which may lead to their failure. Especially, structural integrity of MLG and wing components is decreased as the flight time increased because of the fatigue damage accumulated on the aircraft. In this study, the effects of Hard Landing on the MLG and wing components of aging aircraft were evaluated by using numerical approach. To achieve the aim, a finite element model has been developed and simulations were conducted by varying the landing conditions. As a result, it was revealed that the high stress concentration phenomenon was occurred at the lower Side Brace of MLG. Thereby, the intensified inspection for the lower Side Brace should be considered to prevent unexpected aircraft mishap.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.54 no.8
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• pp.495-497
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• 2005

Recently Neural Network techniques have widely used in adaptive and learning control schemes for production systems. However, generally it costs a lot of time for learning in the case applied in control system. Furthermore, the physical meaning of neural networks constructed as a result is not obvious. And this method has been used as a learning algorithm to estimate the parameter of a neural network used for identification of the process dynamics of s signal input and signal output system and it was shown that this method offered superior capability over the conventional back propagation algorithm. This controller is designed by using three-layered neural networks. The effectiveness of the proposed Neural Network-based control scheme is investigated through an application for a production control system. This control method can enable a plant to operate smoothy and obviously as the plant condition varies with any unexpected accident. This paper goal estimate input signal about controller using neural networks.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2004.11a
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• pp.195-200
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• 2004

To avoid an unexpected explosion occurring from a mixture of LOx and fuel, Inter-Propellant Seal (IPS) is used in a Turbopump. This paper presents a brief theoretical backgrounds of IPS and also reports preliminary test results. Tests were performed up to 1.5 MPa and 20,000 rpm and leakage performance of IPS was evaluated. As a result it was verified that leakage flow rate of IPS satisfied its design requirement.

• Asian Journal of Business Environment
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• v.4 no.4
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• pp.5-11
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• 2014

Purpose - The paper aims to study strategic enterprise resource initiative formation processes. It analyzes the process of managing the strategic resource initiative and discusses its implementation mechanism. A research model for enterprises' strategic development is proposed, which suggests a geometric interpretation for estimating a company's long-term development. Research design, data, and methodology - The analysis employs theoretical studies of modern researchers. The main models used to determine the optimal alternative business strategy are graphic interpretation and mathematical modeling. Results - The hypotheses testing demonstrates the definition of a company's strategic resource initiative and explains the-mechanism or design of its formation. The study presents a geometric prism-refraction model of practice using a strategic resource initiative. Conclusions - An enterprise's strategy could return to its initial state in case of its unexpected deviation as a result of passing through the nodal points. The proposed model allows us to evaluate business performance, its surrounding environment, and the resource management strategy, to determine the necessary scope of strategy changes necessary to bring it back to the original state.