• Proceedings of the KIEE Conference
• /
• 1996.07a
• /
• pp.382-384
• /
• 1996

This paper introduces the controller development of booster multi-pump system with constantly estimated control algorithm. Through analyzing by the experiment of optimal pressure with a certain flow rate. The larger pressure processing apparatus in microprocessor makes optimal water-supplying. This method is implemented with the only pure control algorithm without any other mechanical or circuitry apparatus. Also, Pump's life is lengthened by exchanging simple on, off and rotational inverter control. Optimal condition for pump is adjusted by the inverter control, and compact control panel helps the booster system install in real field.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.16 no.6
• /
• pp.514-521
• /
• 2004

Waste heat recovery system was studied numerically and experimentally. Heat exchanger system was designed specially to obtain the optimum heat exchanging performance. Brushwood biomass was used for the present experimental study. Two biomass heat recovery systems were designed and developed. Polyethylene helical pipe line of 0.03 m (inner diameter) was installed to recover the heat of biomass dump. The fermentation process of biomass dump was maintained for 12 weeks. The inner average temperature of biomass was about 51$^{\circ}C$ for both hot exchanger systems. The current heat recovery system could recover up to 6 ㎉/kg of energy.

• Transactions of the Korean hydrogen and new energy society
• /
• v.31 no.3
• /
• pp.302-306
• /
• 2020

In this study, computer simulation works using PRO/II with PROVISION V10.2 have been performed for a cascade refrigeration cycle using methane, ethylene and propane as refrigerants. LNG cold heat was also utilized in order to save the compression powers for the ethylene and propane refrigeration cycles. It was concluded that about 77% of compression power can be saved by using LNG cold heat through the exchanging heat with refrigerants. We could also know that the cold heat price contained in 1 ton of LNG is 16,155 won.

• Asia pacific journal of information systems
• /
• v.25 no.4
• /
• pp.719-745
• /
• 2015

Social networking services provide individuals with an easy approach for exchanging messages with others based on interpersonal relationships. However, why individuals spread marketer-generated content (MGC) in their online social circles remains unclear. Therefore, we develop a theoretical model to examine how social capital, intrinsic motivations, personal perceptions, past behavior, and personal traits influence MGC sharing behavior of social media users in micro-blogging context. Data collected from 319 social networking users support the proposed model. The results from partial least squares analyses show that enjoyment, perceived control, and outcome expectations are significant indicators of individual's MGC sharing intention in the social broadcasting environment. Results also suggest that social capital, users' intention, and past behavior positively influence the MGC sharing behavior of users. Moreover, individual prevention pride exhibits a significant interaction effect on the relationships between users' MGC sharing and its antecedents. Implications for research and practice are discussed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.05a
• /
• pp.356-359
• /
• 2005

Ionic-polymer-metal-composite(IPMC), one of new actuation materials of electroactive polymers plated with noble metallic electrodes is known for the fast bending upon electric field. The IPMC strip bends towards anode under electrical field. It has many merits of low driving voltage, quick responsiveness, high durability, possibility of miniaturizability. In this paper, we studied for developing the large deflection of IPMC according several fabricating parameters. We measured the large deflection by the different process of sandpaper and sandblasting in surface treatment, the initial compositing process and the surface electroding process, and the different counter ions in ion exchanging process. In fundamental, the displacement of IPMC strip depends on voltage magnitude and applied signal frequency and its maximum deformation is observed at a critical frequency, resonant frequency.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
• /
• 2001.06a
• /
• pp.3121-3121
• /
• 2001

The factors involved in development of electronic grading systems for commodities such as grains and seeds include determination of the factors that influence the end-product utilization of the commodities, and the degree to which these can be predicted by electronic methods. The possibility of exchanging existing methods of grading by electronic methods has to be considered. The respective merits of techniques such as Digital Imaging and Near-infrared (NIR) spectroscopy have to be considered. Digital Imaging is a computerized version of visual inspection and grading, whereas NIR spectroscopy has the potential for grading on the basis of composition and functionality, Selection and evaluation of NIR instruments is an important factor, as are sampling and sample presentation to electronic instruments, and particularly the engineering involved in sample presentation. Sample assembly, and software for calibration development are described in the presentation. Finally the impact and implications of introduction of electronic grading are discussed with particular attention to marketing of the commodities.

• The Journal of Society for e-Business Studies
• /
• v.8 no.1
• /
• pp.103-111
• /
• 2003

Nowadays XML is used for exchanging information in e-Commerce, especially B2B. Necessity of XML DBMS has being increased to efficiently process XML data. So a lots of database products for supporting XML are rapidly appeared in the market. In this paper, we made an XML DBMS system based on Generic Data Model. First we developed XML Adaptor based on Generic Data Model and added it on relational DBMS for developing XML DBMS. XML Adaptor is composed of Query Convertor and XML Repository System. The Query Convertor parse commands that are for XML data manipulation and then call the relevant component of XML Repository System for relational database operation. The XML Repository System handles relational database operations such as create, delete, store, and etc. In this way we can use a relational DBMS for manipulation XML data. Therefor we can build more economically XML DBMS.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2003.03a
• /
• pp.18-18
• /
• 2003

Natural clays are composed of oxide layers whose thickness is about 1nm and cations existing between the layers. A number of these layers makes primary particles with a height of about 8∼10nm and these primary particles make aggregates with a size of about 0.1∼10$\mu\textrm{m}$. When layered silicate was made to be organophilic, by exchanging the interlayer cations with organic cationic molecules, the matrix polymer can penetrate between the layers to give a nanocomposite, where 1nm-scal clay layers exist separately in a continuous polymer matrix. These nanostructured hybrid organic-inorganic composites have attracted the great interest of researchers over the last 10 years. They exhibit improved performance properties compared with conventional composites, because their unique phase morphology by layer intercalation or exfoliation maximizes interfacial contact between the organic and inorganic phases and enhances interfacial properties. Since the advent of nylon-6/montmorillonite nanocomposite developed by Toyota Motor Co., the studies on layered silicate-polymer nanocomposites have been successfully extended to other polymer systems. They greatly improved the thermal, mechanical, barrier, and even the flame-retardant properties of the polymers.

• Proceedings of the KIEE Conference
• /
• 2008.09a
• /
• pp.305-307
• /
• 2008

Inundation of substation and ground power equipment breaks out every summer season in low-lying downtown and low-tying shore by heavy rain, typhoon and tidal wave. In case inundation excluding the exchanging cost of equipment, it occurs a great economic and social loss owing to recovery time and events of electric shock occur by inundation electrical equipment (Pad-mounted Transformer and Switch). So we research the flooding prevention countermeasures of electrical facility and Transformer Vault on Foreign. We conform the site facility and related regulation for flooding prevention on Foreign.

• Journal of Korean Institute of Industrial Engineers
• /
• v.23 no.3
• /
• pp.597-608
• /
• 1997

Life cycle product data is very important yet difficult to handle for manufacturing companies. Shoring and exchanging product data over world-wide-web is a part of key technology to implement PDM or CALS. STEP is widely accepted as a standard to represent the life-cycle product model data. Described in this paper is a web browser plug-in that can graphically display and explore product data represented by STEP over internet. By the use of the plug-in (named "npSTEP"), a product model data stored in STEP format on a web server can be displayed on a commonly used web client (browser), such as Netscape navigator, without any format conversion process. Furthermore one can explore the components or attributes of the product model data in hierarchical manner.