• Journal of Pharmaceutical Investigation
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• v.40 no.4
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• pp.201-212
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• 2010

Self-organized nanogels from polysaccharide derivatives offer a promising approach in treatment of cancer due to their flexibility in chemistry and their ability to improve the therapeutic index of a drug by modifying biodistribution by their preferential localization at target sites and lower distribution in normal healthy tissues. These properties have promoted studies of active cancer targeting by self-organized nanogels for even better accumulation in solid tumors. However although many researchers have reported their potential by using cell culture systems and small animal tumor models in cancer therapy, these nanogels need more decoration such as conjugation with targeting moiety and endowment of stimuli-sensitivity for precise targeting of the cancer site. In this review, we summarize the recent efforts in developing novel targeting approaches via active endocytosis and stimuli-sensitive systems responding to hyperthermic or acidic tumor pH conditions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.108-111
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• 2003

Currently, molecular devices are reported utilizing active self-assembled monolayers containing the nitro group as the active component, which has active redox centers[1]. We confirm the electrical properties of 4,4-di(ethynylphenyl)-2'-nitro-1-benzenethiolate. To deposit the SAM layer onto gold electrode, we transfer the prefabricated Au(111) substrates into a 1mM self-assembly molecules in THF solution. Au(111) substrates were prepared by ion beam sputtering method of gold onto the silicon wafer. As a result, we measured current-voltage curve using ultra high vacuum scanning tunneling microscopy (UHV STM), I-V curve also clearly shows several current peaks between the negative bias region (-0.3958V) and the positive bias region (0.4658V), respectively.

• Journal of IKEEE
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• v.26 no.3
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• pp.483-487
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• 2022

In this paper, we design a self-powered Arduino system for solar energy harvesting and explain its operation. To perform the operation, the Arduino system senses the amount of solar energy that changes every moment and adjusts the ratio of the active mode and sleep mode operation time according to a given solar light intensity. If the intensity of sunlight is strong enough, the Arduino system can be continuously driven in active mode and receive sufficient power from sunlight. If not, the system can run in sleep mode to minimize power consumption. As a result, it can be seen that energy consumption can be minimized by reducing power consumption by up to 81.7% when using sleep mode compared to continuously driving active mode. Also, when the light intensity is at an intermediate level, the ratio between the active mode and the sleep mode is appropriately adjusted according to the light intensity to operate. The method of self-control of the operating time ratio of active mode and sleep mode, proposed in this paper, is thought to be helpful in energy-efficient operation of the self-powered systems for wearables and bio-health applications.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.57-60
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• 2005

We have recently developed new organic TFT technologies such as self-aligned self-assembly (SALSA) process and a high-resolution color active-matrix LCD panel. A new method to realize high-resolution printable organic TFT array to drive active-matrix flat-panel display will be discussed.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.15 no.1
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• pp.6-13
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• 2008

Purpose: This research was conducted to identify major factors that influence competency for nursing students in basic nursing skills. Method: Data were collected by questionnaires from 290 first year students in one college of nursing. The instrument tools included motivation for admission to nursing, concern about fundamentals of nursing, perceived importance of fundamentals of nursing, level of active participation in fundamentals of nursing, number of times to use open Lab, Lab class satisfaction, self-efficacy, self-evaluation and student attitude. Results: There was no significant correlation between competency in basic nursing skills and motivation for admission to nursing, concern about fundamentals of nursing, perceived importance of fundamentals of nursing, or number of times to use open Lab. Competency in basic nursing skill in these students showed a significantly positive correlation to Lab class satisfaction, self-efficacy, self-evaluation, student attitude and level of active participation in fundamentals of nursing. The major factors that influenced competency in basic nursing skills for nursing students were student attitude, self-efficacy and number of times to use open Lab. These factors explained 15.5% of the variance in competency. Conclusion: Basic nursing skill practice education programs should be developed to improve self-efficacy and active participation.

• Proceedings of the KIEE Conference
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• summer
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• pp.1235-1238
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• 2004

This paper presents the large-signal transient analysis of a self-driven active-clamp forward converter, eliminating the extra drive circuit for the active clamp switch. The operation principle of the converter was presented and experiential results were used to verify the analyzed results. A 50-W prototype converter built and tested it. From the tested results, input transient response and load transient response of the converter were established.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.132-134
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• 2000

This paper presents self-oscillating mixer(SOM) with simple structure which includes dc source, a cross type groove, and a three terminal GaAsFET. By using parasitic elements such as cooper wires, If level of the active antenna is increased. In order to include active device into FDTD analysis, equivalent voltage source are used to substitute for the active device and to describe the voltage-current relationships. This approach is applied to analyze SOM theoretically.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.11 no.8
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• pp.338-348
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• 2001

A hybrid self-hearing motor, which Is a functional combination of general permanent magnet (PM) motor and hybrid active magnetic bearing(AMB), was proposed a few years ago. In this paper the hybrid self-bearing motor is modified to a disk type, in which one of two magnetic hearings was substituted for a thin yoke to make the system more compact. An outer rotors in this self-hearing motor is actively controlled only in two radial directions while the ocher motions are passively salable owing to the disk-type structure. Main advantages of the proposed self-hearing motor are simple control mechanism, low power consumption and smart structure. Mathematical model for the magnetic force Is built wish consideration of the radial displacement of the rotor. The model helps us not only to design a levitation controller but also to expect the system performance. Some experimental results show good capability and feasibility of the Proposed self-bearing motor.

• The Research Journal of the Costume Culture
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• v.18 no.5
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• pp.991-1002
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• 2010

Nowadays, personal media is a new tool for communication as digital cameras and mobile phones are developing rapidly. We are concerned over Cyworld users who could have different personal characteristics which will influence on buying patterns in on line shopping behaviors. The purpose of this research was to observe fashion attitudes and purchase behavior of Cyworld mini homepage users, for establishing marketing strategies by understanding consumers. For this study, one line survey was used for 500 male and female subjects who are 20 to 40 years old. Only reliable 441 questionnaires were used for analysis. The SPSS program was used for frequency, K-means cluster, t test, and chi-square test. A total of 441 respondents were clustered on the basis of 8 item self-disclosure scale, using the K-means procedures. The results indicated that respondents were clustered into two segments; 267 respondents(active attitude towards self-disclosure) and 164 ones(not active). We examined fashion attitudes in mini home page and buying behavior by self-disclosed variable. Those who are involved actively in self expression and self-disclosure considered more fashion style and trend. The major motivates of web surfing was finding a good design, and good price. High self-disclosure group tends to search many shopping mall for right design and low self disclosure group tends to search them for the right price. High self-disclosure group tend to shop the fashion products more, while low self disclosure group tend to purchase books more through the internet. We realized that active group in self-disclosure purchased their clothing accidently when they visit Cyworld.

• Smart Structures and Systems
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• v.20 no.3
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• pp.285-301
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• 2017

This paper presents the design and the application of a new self-powered hybrid electromagnetic damper that can harvest energy while mitigating the vibration of a structure. The damper is able to switch between an energy harvesting passive mode and a semi-active mode depending on the amount of energy harvested and stored in the battery. The energy harvested in the passive mode resulting from the suppression of vibration is employed to power up the monitoring and electronic components necessary for the semi-active control. This provides a hybrid control capability that is autonomous in terms of its power requirement. The proposed hybrid circuit design provides two possible options for the semi-active control: without energy harvesting and with energy harvesting. The device mechanism and the circuitry that can drive this self-powered electromagnetic damper are described in this paper. The parameters that determine the device feasible force-velocity region are identified and discussed. The effectiveness of this hybrid damper is evaluated through a numerical simulation study on vibration mitigation of a bridge stay cable under wind excitation. It is demonstrated that the proposed hybrid design outperforms the passive case without external power supply. It is also shown that a broader force range, facilitated by decoupled passive and semi-active modes, can improve the vibration performance of the cable.