• Biomedical Science Letters
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• v.27 no.1
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• pp.1-11
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• 2021

Cancer stem cells, which are known to drive tumor formation and maintenance, are a major obstacle in the effective treatment of various types of cancer. Trans-membrane glycoprotein mucin 1 antigen and cell surface glycogen CD44 antigen are well-known surface markers of breast cancer cells and breast cancer stem cells, respectively. To effectively treat cancer cells and cancer stem cells, we developed a new drug-encapsulating liposome conjugated with dual-DNA aptamers specific to the surface markers of breast cancer cells and their cancer stem cells. These two aptamer (Apt)-targeted liposomes, which were prepared to encapsulate doxorubicin (Dox), were named "Dual-Apt-Dox". Dual-Apt-Dox is significantly more cytotoxic to both cancer stem cells and cancer cells compared to liposomes lacking the aptamers. Furthermore, we demonstrated the inhibitory efficacy of Dual-Apt-Dox against the experimental lung metastasis of breast cancer stem cells and cancer cells in athymic nude mice. We also showed the potent antitumor effects of dual-aptamer-conjugated liposome systems by targeting cancer cells as well as cancer stem cells. Thus, our data indicate that dual-aptamer-conjugated liposome systems can prove to be effective drug delivery vehicles for breast cancer therapy.

• Journal of Convergence for Information Technology
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• v.11 no.4
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• pp.161-167
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• 2021

This study was conducted to identify the relationship between the dual task performance and driving behavior of the elderly driver in order to identify whether the dual task can be utilized as a test to screen the driving ability of the elderly driver. We surveyed general information and driving-related information for 32 normal elderly drivers, and evaluated Y-DuCog(Yonsei-Dual task Cognitive screening) and the K-DBQ (Korean-Driving Behavior Questionnaire). As a result of the study, the performance of the dual task using the pegboard task and the animal name speaking showed a significant correlation with the score of the violation domain of K-DBQ. With this study, it was possible to confirm the possibility as a test for discrimination of driving ability.

• PNF and Movement
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• v.20 no.2
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• pp.243-251
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• 2022

Purpose: This study aimed to compare the effects of aquatic and land dual-task training on balance, gait, and depression in chronic stroke patients. Methods: A total of 24 patients diagnosed with chronic stroke were the subjects. They were assigned to either the experimental group (n = 12) or the control group (n = 12). The experimental group performed aquatic dual-task training, while the control group performed land dual-task training. The aquatic and land dual-task training sessions were conducted once a day for 30 min, 5 days per week, for 6 weeks. Balance was measured using the Berg balance scale. Gait was measured using the Timed Up and Go Test. The Beck's Depression Inventory was used to measure depression. Results: Both the experimental and control groups showed significant differences in balance, gait, and depression after the intervention (p < 0.05) in the within-group comparisons. It was found that the experimental group showed more significant differences in balance, gait, and depression than the control group (p < 0.05) when the two groups were compared. Conclusion: It can be concluded that aquatic dual-task training effectively improved the balance ability, gait ability, and chronic stroke patients' depression based on these results.

• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.2
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• pp.112-121
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• 2001

From the beginning of 1990s, the leading countries, especially United States, are trying to develop dual-use technology which can be used for both military and commercial purpose, and to improve the efficiency of management system in logistics and procurements. Considering the global trends, Department of Defence has been seeking for solutions as to how to reform military specifications, and launched specification unification projects. As a result of the project, a series of dual-use standards for hardwares are being developed in the form of Korea Industrial Standards(KS standards). However, there are many of foreign standards, which are not readily interpretable by users, referenced in the standards. In this study, needs for the conversion of referenced foreign standards to KS standards are reviewed and the appropriate approaches as to the conversion are suggested.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1309-1314
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• 2003

The high precision positioning mechanism is used in various industrial fields. It is used in semiconductor manufacturing line, test instrument, Bioengineering, and MEMS and so on. This paper presents a positioning mechanism with dual servo system. Dual servo system consists of a coarse stage and a fine motion stage. The course stage is driven by VCM and the actuator of fine stage is the PZT. The purposes of dual servo system are stability, higher bandwidth, and robustness. Lead compensator is applied to this control system, and is designed by PQ method. Designed compensator can improve property of positioning mechanism.

• The Transactions of the Korean Institute of Power Electronics
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• v.17 no.2
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• pp.142-149
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• 2012

The independently regulated dual-output LLC resonant converter using only one power stage and one control IC is proposed in this paper. The conventional dual-output LLC resonant converter requires the extra non-isolated DC/DC converter to obtain the tightly regulated slave output voltage, which results in the low power conversion efficiency and high production costs. On the other hand, since the proposed converter controls the master and slave output voltages by pulse width modulation(PWM) and pulse frequency modulation(PFM), it can achieve tightly regulated dual output voltages without the additional non-isolated DC/DC converter. Therefore, it features a high efficiency and low cost. To confirm the validity of the proposed converter, theoretical analysis and experimental results from a 40W LED driver prototype are presented.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.6
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• pp.1433-1442
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• 1998

The thesis presents a dual audio decoder which can decode both AC-3 and MPEG-2 bitstream. The MPEG-2 synthesis processi s optimized via FFT to establish the common data path with AC-'3s. A dual audio decoder consists of a DSP core which performs the control-intensive part of each algorithm and a common synthesis filter which perfomrs the computation-intensive part. All the components of the dual audio decoder have been described in VHDL and simulated with a SYNOPSYS tool. The software modeling of the DSP core was used for functional validation. After being synthesized using 0.6 .mu.m-3ML technology standard cell, the dual audio decoder was simulated at gate-level with a COMPASS tool for hardware validation.

• Journal of electromagnetic engineering and science
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• v.13 no.2
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• pp.104-112
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• 2013

A novel miniaturized artificial magnetic conductor (AMC) is proposed for dual-band operation. An AMC unit cell that employs four slots in the metallic patch is used to achieve miniaturization as well as easy control of the second/first resonant frequency ratio, which can be varied from 1.5 to 3.26 by simply changing the slot shape for a given metallic patch size. A dual-band antenna composed of a wideband monopole suspended over the proposed AMC surface is designed and tested to validate this approach. The measurements result in a satisfactory and good matching condition for the dual-band antenna.

• The Transactions of the Korean Institute of Power Electronics
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• v.20 no.6
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• pp.573-579
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• 2015

A control algorithm of thyristor dual converter power system is proposed in this study for a railway power substation. The thyristor dual converter can use regenerative power without an additional system using control algorithm. An autonomous voltage and mode change method is also proposed to provide uninterrupted power to the railway. A 10 kW reduced model of the thyristor dual converter power system is built and tested to verify the validity of the proposed control algorithm.

• Journal of ILASS-Korea
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• v.10 no.2
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• pp.32-40
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• 2005

This paper presents the analytical approaches to predict cutting fluid aerosol formation characteristics in machining process. The prediction model which is based on the rotary atomization theory analyzes aerosol behaviors in terms of size and concentration. Experiments were tarried out to verify the aerosol formation prediction model under various operational conditions. The experimental results which are obtained by Dual-PDA measurement show resonable agreement with prediction results of aerosol concentration. This study can be provided as a basis to estimate and control the hazardous cutting fluid aerosol in machining process in view of environmental consciousness.