• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2004년도 한국우주과학회보 제13권1호
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• pp.70-70
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• 2004

Lower thermospheric winds are forced primarily by non-uniform solar heating, atmospheric tides and other waves coming from below, and energy and momentum forcing associated with high-latitude magnetosphere-ionosphere coupling, particularly ion drag and Joule heating. To understand the physical processes that control the thermospheric dynamics, we quantify the momentum forces that are mainly responsible for maintaining the high-latitude lower thermospheric wind system and examine the resulting momentum balance with the aid of the Thermosphere-Ionosphere Electrodynamics General Circulation Model (NCAR-TIEGCM) developed by the National Center for Atmospheric Research. (omitted)

• Journal of Advanced Marine Engineering and Technology
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• 제27권2호
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• pp.305-311
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• 2003

This Paper Presents an information about the heat transfer characteristics of a separate type thermosyphon in electronic equipments. The heat removal problem of electronic equipments is regarded as an important factor and a separate type heatpipes can be utilized as a cooling device of electronic equipments (such as CPU of a Personal computer or notebook). In this study. heat source ($50\times50\times2 mm $aluminum Pseudo CPU) was used for the experiment. The device can transfer heat from the evaporator to the condenser through natural circulation (without any external driving forces) and the results indicate that the device is capable of dissipating over 60W of thermal energy and keeping the heating plate surface temperature under $50^{\circ}C$.

• 대한기계학회논문집B
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• 제29권5호
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• pp.554-560
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• 2005

A new method to improve the efficiency of a hydrogen fuel cell system was introduced by using variable sonic/supersonic ejectors. To obtain the variable area ratio of the nozzle throat to ejector throat which controls the mass flow rate of the suction flow, the ejectors used a movable cylinder inserted into a conventional ejector-diffuser system. Experiments were carried out to understand the flow characteristics inside the variable ejector system. The secondary mass flow rates of subsonic and supersonic ejectors were examined by varying the operating pressure ratio and area ratio. The results showed that the variable sonic/supersonic ejectors could control the recirculation ratio by changing the throat area ratio, and also showed that the recirculation ratio increased fur the variable sonic ejector and decreased for the variable supersonic ejector, as the throat area ratio increases.

• 신재생에너지
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• 제4권4호
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• pp.17-22
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• 2008

A low concentrating (< 5X) photovoltaic module with aluminum reflectors is fabricated and evaluated which is designed to reduce the affection of the high temperature to the solar cell modules preventing the efficiency lowering. As results, the output power is increased of 1.97X from the concentrating photovoltaic module which is designed with the concentrating ratio of 2.25X and to control the module temperature cooling the module by air circulation. Also, the effect of the concentrating module with aluminum reflectors on the conventional PV module is investigated at the field. The result shows the increase of the output power more than about 20% and the improvement of the module efficiency of 1.4X in spite of the increase of average module temperature.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 1999년도 춘계학술대회 발표논문집
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• pp.30-35
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• 1999

Recently, many companies want to accept and operate ERP(Enterprise Resource Planning) system in their fields ERP does not only include business, but also include finance, account, trade, personnel and BPR(Business Process Reengineering). Especially, it is necessary to have ERP system for companies which have lots of external businesses such as trade and communication sector. In modern society, the manufacture field faces on variable chances of Environment. For this situation, the application of Information technique is one of the main point maintain competitive power. The company should chose a proper method for their future and build Unified Information System on its suitable situation. Nowadays, Adjustment and application of technical method for Internet/Intranet and raised and more advanced Extranet gains its force at the moment. The Unification of ERP and POP system under the distributed environment like this will have a huge influence to us. In this subject, I will think about POP system for operating EPR system and improve its defects that can operate more effective sales, circulation, demand plan. Also, I suggest a proper POP system can handle seperated resources in each part of factory for a plan of shot period, order operating, factory inventory, process control.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.380-382
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• 2007

As the society changes more to the aging society in future, many healthcare product are developed and distributed more on the market. The digital wrist band tye blood pressure device for home use are popular already in the market. It is useful for checking blood pressure level at home and control of hypertension. Especially. It is very essential home device to check the health condition of blood circulation disease. Nowadays many product types are available. But the measurement accuracy of blood pressure is not enough compared to the mechanical type. It needs to be upgraded to assure the precise health data enough to use in the hospital. The structure, feature and output signal of capacitor type pressure sensors are analyzed. An improved design fa capacitor sensor is suggested. It shows more precise health data after use on a wrist band type health unit. They can be applied for remote u-health medical service.

• 한국한의학연구원논문집
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• 제9권1호
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• pp.129-135
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• 2003

Rehmanniae Radix Preparata attributes good blood circulation and it has been used for the treatment of dizziness, men's sterility, excessive loss of blood and weakness. On the quality control of commercial Rehmanniae Radix Preparata, quantitative determination of 5-hydroxymethyl (5-HMF) using HPLC method has been conducted. Quantitative analysis of S-hydroxymethyl-2-furaldehyde (5-HMF) in commercial Rehmanniae Radix Preparata showed average of $0.136{\pm}0.057%$ in 14 samples collected throughout the regions of Korea.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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• pp.957-960
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• 2003

Many solar cell way need to be connected by series or parallel to extract the high power Especially, during parallel operation to reduce circulation current the individual converter has to share and control the load current. Generally, Current Sharing(CS) can be implemented using droop and active current sharing method. In this paper, one 3[KW] PWM converter was replaced as one 3[KW] solar cell array(3 parallels, each parallel has twenty single modules), two 3[KW] solar cell way Is Paralleled to generate 6[KW] power. Also each converter used voltage-current controller and Automatic MSCPM(Master-Slave Current-programming Method) for current sharing(AS).

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.3-6
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• 2002

In this paper, the electrolyte flow treatment is suggested using together with needle and magnet. On account of Lorentz force law, we can not only induce the circulation of body fluids at specific hurt but also apply on the treatment of cell membrane voltage control controlling the electrolyte flow. If electric field is added to human body fluid, electrolyte and then magnetic field is taken by magnet, we can induce local region flow through needle, global region flow with artificial electrical field and magnetic field. Electrolyte flow is excellent treatment in clinical treatment.

• Ocean and Polar Research
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• 제27권2호
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• pp.183-188
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• 2005

Using data from Argo floats collected in the Southern Ocean, we describe water mass prop erties and flow fields at intermediate levels (1000m and 2000m levels). Water mass properties from Argo floats, which are consistent with those from previous hydrographic surveys, reflect the movement of the floats well even without quality control on the Argo data. Since the flow fields from the Argo floats do not cover the entire Southern Ocean, we could not obtain a general circulation pattern, especially at the 2000m level. We, however, can confirm the general eastward tendency due to ACC largely following the topography.