• Journal of Environmental Science International
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• v.18 no.1
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• pp.9-14
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• 2009

Pfiesteriaand Pfiesteria-like organisms were reported to be linked to major fish kills(involving well over a billion fish) in North Carolina and Maryland estuaries on the U.S. east coast during the 1990s. Occurrences of these species have been recently reported from Korean waters including Chinhae Bay and the coast of Yeosu. In this study, the life cycle of Cryptoperidiniopsis brodyi and Pfiesteria piscicida were examined using DAPI staining. Their excystment and growth were stimulated directly by the addition of prey cells such as Rhodiminas salina. Amoeboid stages in C. brodyi and P. piscicida were never observed in culture, even after addition of filter-sterile fish mucus and tissue. The dominant life cycle stages consisted of motile flagellated zoospores and cysts. A typical dinoflagellate life cycle was demonstrated by direct observation and DAPI staining.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.11
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• pp.1300-1305
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• 2009

The various electromagnetic based actuation(EMA) methods have been proposed for actuating microrobot. The advantage of EMA is that it can provide wireless driving to microrobot. In this reason a lot of researchers have been focusing on the EMA driven microrobot. This paper proposed a swimming microrobot driven by external alternating magnet field which is generated by two pairs of Helmholtz coils. The microrobot has a fish-like shape and consists of a buoyant robot body, a permanent magnet, and a fin. The fin is directly linked to the permanent magnet and the magnet is swung by the alternating magnet field, which makes the propulsion and steering power of the robot. In this paper, firstly, we designed the locomotive mechanism of the microrobot boy EMA. Secondly, we set up the control system. Finally, we demonstrated the swimming robot and evaluated the performance of the microrobot by the experiments.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.275-277
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• 2015

This paper proposed have been the business card information to the computer when creating business card printing agency saved to a file, there is always the risk of personal information leakage. Application file organization information into the card, the name, phone number, email address information, such as is capable of easily accessible because it is not encrypted. This paper proposed it encrypts the information entered on the Business Card application file to automate the process of the card application and simplifying the business card application process minimizes the work of staff and linked directly to the print shop how to automatically delete the print file after the completion of business card printing and research.

• Fashion & Textile Research Journal
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• v.11 no.5
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• pp.741-752
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• 2009

As a major obstacle to active online purchase at the level of consumer in China, distrust is raised in this study. Most of previous studies showed that trust is a major variable to cause a relational unity between company and consumer, on the other hand, this study attempts to show that according to the two dimensional point of view regarding trust each dimension of both trust and distrust distinctly contributes to marketing achievement. Interaction, perceived popularity, information usefulness, perceived security risk and perceived dealing risk were created as preceding variable, trust and distrust were constituted as parameter and relation absorption and purchase intention as consequential variable. These variables were analyzed with structural equation modeling (SEM) in LISREL 8.3 program. The results for this study are as follows. First, relation between exchange actors in marketing is divided into two concepts of trust and distrust differently from the previous studies. On the assumption that trust and distrust might exist simultaneously and they would distinctly have an influence on marketing consequency such as relation absorption and repurchase intention, it is identified that trust and distrust are a different dimension in online context. Second, the formative factor of online trust-distrust is identified and it is shown what relationship between internet shopping mall and relation absorption and foregoing purchase intention resulting from online trust-distrust exists. Third, it is shown that in online context the formative factor of online trust-distrust is distinctly contributed to relation absorption and repurchase intention. It is suggested that trust needs to be managed two-dimensionally separating from trust and distrust. Fourth, it is shown that both trust and distrust factor in terms of relation absorption and repurchase intention of consumer in internet shopping mall are significant variables. Trust is linked with repurchase intention through relation absorption, however, distrust is not directly linked with repurchase intention through relation absorption. Thus, the ripple effect of distrust appears to be much higher than that of trust.

• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.1
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• pp.141-153
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• 2016

The increase in frequency and scale of natural disasters is the typical negative examples of the global climate change and the change of the human living environment in cities. The damage caused by natural disasters in particular including human and physical damage is directly linked to the safety and properties of citizens. Besides, the damage may occur to SOC facilities directly or indirectly. The SOC facilities damaged by disasters cause infringement of citizens safety rights. Therefore, a plan to provide prompt and effective risk map information by linking a 3D disaster information display system, which handles the information of the damage that may occur to SOC facilities such as bridges, beams, and dams at the time of disasters, with an on-site assistance application is suggested in this study. The prompt provision of risk map information is defined as a dynamic expression technology in this study. Also, disaster information is processed and compressed with a module developed to be linked organically to a system that displays disaster information, a proliferation system that can use the information on site, and a DB system that constructs a relationship with the information. Based on the module, the effective disaster information compression plan will be prepared, and the prompt information transmission system will be secured in the future.

• International Journal of Precision Engineering and Manufacturing
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• v.2 no.1
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• pp.43-55
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• 2001

A continuously variable transmission(CVT) mechanism composed of one differential gear unit and one continuously variable unit(CVU) can be classified according to the coupling of CVU and the direction of power flows. The mechanism has many advantages which are the decrease of CVT size, the increase of overall efficiency, the extension of speed ratio range and generation of geared neutral. The CVT mechanism considered here is the input coupled type which combines the functions of a 2K-H I type differential gear unit and a V-belt type CVU. One shaft of the CVU is connected directly to the input shaft and another shaft of it is linked to the differential gear unit. It is shown that some fundamental relations(speed ratios, power flows and efficiencies) for twelve mechanisms previously described are valid by various experimental studies, six of them produce a power circulation and the others produce a power split. Some useful comparisons between theoretical analysis and experimental results are presented. General properties also are discussed, which connect following power flow modes : (a) power circulation mode; (b) power split mode.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.7
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• pp.7-15
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• 2008

A single active capacitor snubber-assisted soft-switching sinewave pulse modulation utility-interactive power conditioner with a three-winding flyback high frequency transformer link and a bidirectional active power switch in its secondary side has been proposed. With the aid of the switched-capacitor quasi-resonant snubber cell, the high frequency switching devices in the primary side of the proposed DC-to-AC sinewave power inverter can be turned-off with ZVS commutation. In addition to this, the proposed power conditioner in the DCM can effectively take the advantages of ZCS turn-on commutation. Its output port is connected directly to the utility AC power source grid. At the end, the prototype of the proposed HF-UPC is built and tested in experiment. Its power conversion conditioning and processing circuit with a high frequency flyback transformer link is verified and the output sinewave current is qualified in accordance with the power quality guidelines of the utility AC interactive power systems.

• The Korea Journal of Herbology
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• v.21 no.4
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• pp.93-101
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• 2006

Objectives : Increasing evidence has linked chronic inflammation to a number of neurodegenerative disorders including Alzheimer's disease(AD), Parkinson's disease(PD) and Huntington's disease(HD) in the inflammatory process. Uncontrolled activation of microglia may directly toxic to neurons by releasing various substances such as inflammatory cytokines ($TNF-{\alpha}$, $IL-1{\beta}$ and IL-6), NO, PEG2 and superoxide. In this study, the immunomodulatory effects of the herbal extract Panax notoginseng on cultured BV2 microglial cells and primary microglia were investigated to address potential therapeutic or toxic effects. Notoginseng radix extracts extracted from the root of the plant using Methanol. Methods : Cells were stimulated with LPS and treated with notoginseng at different concentrations. Results : Notoginseng significantly decreased LPS-induced production of $TNF-{\alpha}$ and IL-6 by the cultured microglial cells in a dose-dependent manner. The activation of iNOS mRNA and secretion of nitric oxide(NO) in microglial cells were inhibited in microglial cells in a dose-dependent manner by notoginseng. Conclusion : These results indicate that notoginseng inhibits LPS-induced activation of microglial cells and demonstrates notoginseng possess anti-inflammatory and immunosuppressive properties in vitro.

• 한국지구물리탐사학회:학술대회논문집
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• 2006.06a
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• pp.17-22
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• 2006

Shear modulus is directly linked to material's stiffness and is one of the most critical engineering parameters. Seismically, shear-wave velocity (Vs) is its best indicator. Although methods like refraction, down-hole, and cross-hole shear-wave surveys can be used, they are generally known to be tougher than any other seismic methods in field operation, data analysis, and overall cost. On the other hand, surface waves, commonly known as ground roll, are always generated in all seismic surveys with the strongest energy, and their propagation velocities are mainly determined by Vs of the medium. Furthermore, sampling depth of a particular frequency component of surface waves is in direct proportion to its wavelength and this property makes the surface wave velocity frequency dependent, i.e., dispersive. The multichannel analysis of surface waves (MASW) method tries to utilize this dispersion property of surface waves for the purpose of Vs profiling in 1-D (depth) or 2-D (depth and surface location) format. The active MASW method generates surface waves actively by using an impact source like sledgehammer, whereas the passive method utilizes those generated passively by cultural (e.g., traffic) or natural (e.g., thunder and tidal motion) activities. Investigation depth is usually shallower than 30 m with the active method, whereas it can reach a few hundred meters with the passive method. Overall procedures with both methods are briefly described.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.1
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• pp.48-53
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• 2005

This paper aims to compare open source software (OSS) with proprietary software (PS), and to propose a new business model for OSS. Generally speaking, PS has made negative impact on software industry in various ways. In contrast, OSS may reduce negative aspects of lock-in effect and transaction cost the ways in which software distribution has been utilized. In this regard, OSS makes it possible to create a new business model, which is software customization. Software customization is not to sell software license directly to end-users, but to create values by means of developing and capitalizing software-related industries where value chain is linked. In other words, the new business model of OSS is focusing on software market where the value created by OSS can be enhanced.