• Journal of the Korea Society of Computer and Information
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• v.25 no.9
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• pp.81-90
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• 2020

In order to operate multi drone efficiently, existing control methods must be improved, and drones must be able to construct communication networks autonomously. FANET(Flying Ad-Hoc Network), which is being considered as an alternative to solving these problems, is based on ad hoc network technology and can be exposed to a variety of security vulnerabilities. However, due to the limited computational power and memory of FANET nodes, and rapid and frequent changes in network topology, it is not easy to apply the existing security measures to FANET without modification. Thus, this paper proposes lightweight security measures applicable to FANET, which have distinct characteristics from existing ad hoc networks by utilizing PUF technology. The proposed security measures utilize unique values generated by non-replicable PUFs to increase the safety of AODV, FANET's reactive routing protocol, and are resistant to various attacks.

• Journal of the Korean Society for Nondestructive Testing
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• v.17 no.2
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• pp.108-113
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• 1997

Ultrasonic testing is one of the most widely used method of nondestructive testing for pre-service inspection(PSI) & in-service inspection(ISI) in structures of bridges, power plants, chemical plants & heavy industrial fields. It is very important to estimate safety, life, quality of structures. Also, a lot of research for quantities evaluation & analyses inspection data is proceeding. But traditional portable ultrasonic flaw detector had been following disadvantages. 1) Analog ultrasonic flaw detector decreased credibility of ultrasonic test, because it is impossible for saving data & digital signal processing. 2) Stand-alone digital ultrasonic flaw detector cannot effectively evaluate received signals because of lack of its storage memory. To overcome this shortcoming, we develop the computer based ultrasonic flaw detector for nondestructive testing. It can store the received signal and effectively evaluate the signal, and then enhance the reliability of the testing results.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.3
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• pp.284-290
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• 2016

As the recently advanced scientific developments result in high lever of the usability and the needs for the electrical equipment and devices in various situations, the safety technologies protecting malfunction and electrical critical damages including soft and hardware from the unexpectedly radiated electromagnetic interferences are required gradually. In addition, the numerical analysis for the miniaturized electrical components and equipments as well as the conventional electrical devices installed inside the electrically large enclosures and structures requires the memory requirement and time consumption too big to be handled in a realistic situation, which will result in a limitation in solving the complete set of maxwell's equations. In this paper, PWB method based on statistical theory and topological modeling with appropriate zoning concepts are introduced for the EM analysis of an electrically large complex structures.

• Korean Journal of Pharmacognosy
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• v.46 no.3
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• pp.173-188
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• 2015

We have conducted a comprehensive literature review regarding the chemical constituents and biological activities of Korean black ginseng(Panax ginseng C. A. Meyer), three to nine times-steamed and dried ginseng, which shows strong black color through Maillared browning reaction. It has been reported that some chemically deglycosylated and transformed saponins are obtained from black ginseng as artifacts produced during intensive steaming. They have been known to be ginsenosides Rg3, Rg4, Rg5, Rg6, Rh1, Rh2, Rh4, Rk1 and Rk3, quite different from those of red ginseng, among which ginsenosides Rg3, Rg5 and Rk1 are considered to be major components. And also, black ginseng has been recently found to demonstrate anticancer, recovery from learning and memory damages, hypontensive, antidiabetic, antiobesitic, tonic and antiatopic activities, together with antioxidative and exercise performance improving activities, exhibiting their effects to be a little bit stronger than those of red ginseng. These findings suggest that black ginsng might play an important role in the development of promising functional foods and drugs from the viewpoint of the chemical composition and biological activities of black ginseng with a distinction from those of white and red ginsengs. In this review, the authors will survey and evaluate further functions of black ginseng with a focus on its physicochemical properties and biological activities.

• Korean Journal of Adult Nursing
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• v.20 no.4
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• pp.600-612
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• 2008

Purpose: This study was conducted to compare the recovery state of 6 month between s-ICH and s-SAH patients. The patients' recovery state was measured with 2 dimensions: functional and cognitive. Methods: Non-experimental prospective design was adopted by including 108 hemorrhagic stroke patients(s-ICH: 52 vs s-SAH: 56) admitted to Intensive Care Unit of one university hospital. Results: The study results showed that overall functional recovery state of s-SAH patients was better than that of s-ICH patients, and s-SAH patients also showed better recovery states in all of the sub-dimensions of functional recovery, such as feeding, grooming, and toileting, than those of s-ICH in 6 month. On the contrary, the study results showed that overall cognitive recovery states of 6 month between two groups were not significantly different. However, according to the results comparing the sub-dimensions of cognitive recovery, s-SAH patients' recovery states on attention, communication and memory were significantly better than those of s-ICH patients, while recovery states on problem solving, safety behavior, and social behavior between 2 groups were not significantly different. Conclusion: From the study results, it was noted that s-SAH patients showed better recovery states in cognitive dimension as well as in functional dimension compared with s-ICH patients.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.4A
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• pp.473-478
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• 2008

WAVE is a short-to-medium range communication standard that supports both public safety and private operations in roadside-to-vehicle and vehicle-to-vehicle communication environments. The core technology of physical layer in WAVE is orthogonal frequency division multiplexing (OFDM), which is sensitive to timing synchronization error. Besides, minimizing the latency in communication link is an essential characteristic of WAVE system. In this paper, a robust, low-complexity and small-latency timing synchronization algorithm suitable for WAVE system and its efficient hardware architecture are proposed. The comparison between proposed algorithm and other algorithms in terms of computational complexity and latency has shown the advantage of the proposed algorithm. The proposed architecture does not require RAM (Random Access Memory) which can affect the pipe lining ability and high speed operation of the hardware implementation. Synchronization error rate (SER) evaluation using both Matlab and FPGA implementation shows that the proposed algorithm exhibits a good performance over the existing algorithms.

• Journal of Electrochemical Science and Technology
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• v.11 no.4
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• pp.384-391
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• 2020

Due to its characteristics of light weight, high energy density, good safety, long service life, no memory effect, and environmental friendliness, lithium-ion batteries (LIBs) are widely used in various portable electronic products. The capacity and performance of LIBs largely depend on the performance of electrode materials. Therefore, the development of better positive and negative materials is the focus of current research. The application of metal organic framework materials (MOFs) derivatives in energy storage has attracted much attention and research. Using MOFs as precursors, porous metal oxides and porous carbon materials with controllable structure can be obtained. In this paper, rod-shaped Co-MOF-74 was grown on Ni Foam (NF) by hydrothermal method, and then Co-MOF-74/NF precursor was heat-treated to obtain rodshaped Co₃O₄/NF. Ni Foam was skeleton structured, which effectively relieved. The change of internal stress changes and destroys the structural volume of the electrode material and reduces the capacity attenuation. Co₃O₄/NF composite material has a specific discharge capacity of up to 1858 mA h/g for the first time, and a reversible capacity of up to 902.4 mA h/g at a current density of 200 mA/g, and has excellent rate and impedance performance. The synthesis strategy reported in this article opens the way to design high-performance electrodes for energy storage and electrochemical catalysis.

• The Journal of the Korea Contents Association
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• v.12 no.12
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• pp.179-191
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• 2012

In 2003, the US Congress enacted the Code Adam Act of 2003. The Act was so-named in memory of six-year-old Adam Walsh, who was abducted from a Sears department store in Florida and was later found murdered in 1981. According to the Act, the designated authority for a public building must establish procedures for locating a child missing in a federal facility in the USA. In this context, the study basically aims to propose a legislative model for a missing children policy in Korean multi-use facilities, critically analyzing the US Code Adam Act. Unlike the Act, the proposed Korean bill requires all multi-use facilities beyond a certain size, including private buildings, to arrange a feasible missing child procedure on their own premises. The bill can impose an administrative fine on facilities which don't have the procedure in place, and further can make the list of the facilities known to the public. In order to encourage voluntary participation from the private sector, the bill finally suggests the Voluntary Certification Scheme through which participating business can take advantage of the certification logo commercially.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4233-4235
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• 2016

Background: Whole brain radiotherapy (WBRT) and stereotactic radiosurgery were frequently used to palliate patients with brain metastases. It remains controversial which modality or combination of therapy is superior especially in the setting of limited number of brain metastases. The availability of newer medical therapy that improves survival highlighted the importance of reducing long term radiation toxicity associated with WBRT. In this study, we aim to demonstrate the hippocampal sparing technique with whole brain and integrated simultaneous boost Materials and Methods: Planning data from 10 patients with 1-5 brain metastases treated with SRS were identified. Based on the contouring guideline from RTOG atlas, we identified and contoured the hippocampus with 5mm isocentric expansion to form the hippocampal avoidance structure. The plan was to deliver hippocampal sparing whole brain radiotherapy (HSWBRT) of 30 Gy in 10 fractions and simultaneous boost to metastatic lesions of 30 Gy in 10 fractions each. Results: The PTV, hippocampus and hippocampal avoidance volumes ranges between 1.00 - 39.00 cc., 2.50 - 5.30 cc and 26.47 - 36.30 cc respectively. The mean hippocampus dose for the HSWBRT and HSWBRT and SIB plans was 8.06 Gy and 12.47 respectively. The max dose of optic nerve, optic chiasm and brainstem were kept below acceptable range of 37.5 Gy. Conclusions: The findings from this dosimetric study demonstrated the feasibility and safety of treating limited brain metastases with HSWBRT and SIB. It is possible to achieve the best of both worlds by combining HSWBRT and SIB to achieve maximal local intracranial control while maintaining as low a dose as possible to the hippocampus thereby preserving memory and quality of life.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.2
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• pp.94-103
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• 2003

In case of environment requiring safety such as human body and requiring flexible shape, a conventional mechanical actuator system does not satisfy requirements. Therefore, in order to solve these problems. a research of various smart material such as EAP (Electro Active Polymer), EAC (Electro Active Ceramic) and SMA (Shape Memory Alloy) is in progress. Recently, the highest preferring material among various smart material is EP (Electrostictive Polymer), because it has very fast response time, powerful force and large displacement. The previous researches have been studied properties of polymer and simple control, but present researches are studied a polymer actuator. An EP (Electostrictive Polymer) actuator has properties which change variably ils shape and environmental condition. Therefore, in order to coincide with a user's purpose, it is important not only to decide a shape of actuator and mechanical design but also to investigate a efficient controller. In this paper, we constructed the control logic with an adaptive fuzzy algorithm which depends on the physical properties of EP that has a dielectric constant depending on time. It caused for a sub-actuator to operate at the same time that a sub-actuator system operation increase with a functional improvement and control efficiency improvement in each actuator, hence it becomes very important to manage it effectively and to control the sub-system which Is operated effectively. There is a limitation on the management of Main-host system which has multiple sub-system, hence it brings out the Multi-Vehicle Control process that disperse the task efficiently. Controlling the multi-dispersion system efficiently, it needs the research of Main-host system's scheduling, data interchange between sub-actuators, data interchange between Main-host system and sub-actuator system, and data communication process. Therefore in this papers, we compared the fuzzy controller with the adaptive fuzzy controller. also, we applied the scheduling method for efficient multi-control in EP Actuator and the algorithm with interchanging data, protocol design.