• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.13-16
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• 2002

The analysis of characteristics of pumping in the small tube well for agriculture were surveyed. Study area was located at the Galsinri in Yesangun near the yedang reservoir. Agricultural electricity using rates for pumping, ground water level and volume of pumping was monitored every week. Pump working ratio and pump efficiency during period of transplanting of rice showed 48.9%, 62.7% respectively.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.10
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• pp.1899-1909
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• 2007

A cross-coupled charge pump with internal pumping capacitor, witch is advantages from a point of minimizing TFT-LCD driver IC module, is newly proposed in this paper. By using a NMOS and a PMOS diode connected to boosting node from VIN node, the pumping node is precharged to the same value each pumping node at start pumping operation. Since the lust-stage charge pump is designed differently from the other stage pumps, a back current of pumped charge from charge pumping node to input stage is prevented. As a pumping clock driver is located the font side of pumping capacitor, the driving capacity is improved by reducing a voltage drop of the pumping clock line from parasitic resistor. Finally, a layout area is decreased more compared with conventional cross-coupled charge pump by using a stack-MIM capacitors. A proposed charge pump for TFT-LCD driver IC is designed with $0.13{\mu}m$ triple-well DDI process, fabricated, and tested.

• The Journal of Engineering Geology
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• v.18 no.4
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• pp.439-446
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• 2008

We have developed a method to evaluate pumping rates from a system of pumping-well family. For a given system actual pumping rates depend on pump characteristics and the sum of the static head and the dynamic head. The static head is the elevation difference between the natural groundwater level and the outlet of the pipeline that connects all the wells. Major components of the dynamic head are groundwater drawdown in the well and pipeline head loss. The dynamic head and the pump characteristics depend on the pumping rates. Actual pumping rates are determined at the intersections of the system total-head curves and the pump characteristic curves. The Newton-Raphson's method is used to solve the nonlinear simultaneous equations. The method is applied to a hypothetical well family. Impacts of various design and operational parameters on the pumping rates are analyzed.

• Journal of Soil and Groundwater Environment
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• v.19 no.3
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• pp.1-14
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• 2014

It is necessary to decide the pumping rate and pumping well location together with the capture zone in order to determine an appropriate groundwater remediation strategy to manage the contaminated groundwater. The relationship between the capture zone and the drawdown radius of influence ($ROI_s$) was considered. $ROI_{cs}$ is defined as the distance where the criteria of drawdown is cs meter from pumping well in this paper. A method to decide the required pumping rate for the remediation of contaminated groundwater in order to create appropriate $ROI_{cs}$ is suggested by using the Theis equation (1935) and Cooper-Jacob equation (1946). It was shown in this study that $ROI_{cs}$ is in proportion to the pumping rate and the criteria of drawdown, which decides $ROI_{cs}$, is inversely proportional to Ti value (transmissivity ${\times}$ hydraulic gradient). The pumping rate which creates the required $ROI_{cs}$ could be planned through the relationship between the $ROI_{cs}$ and pumping rates ($ROI_{cs}$-Q curve) of the field sites 1, 2 and 3. If the drawdown is investigated along with Ti value and pumping rate at a specific site where pump and treat remediation is planned, it is expected that the required criteria of drawdown can be evaluated by using the relationship between the cs and Ti (cs-Ti curve).

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.87.2-87.2
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• 2005

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.635-638
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• 2001

Photovoltaic (PV) pumping systems with maximum power point tracking (MPPT) technique aims at obtaining the highest possible power to the pump under various insolation and temperature, thus overcomes the mismatch between the photovoltaic panel and the pumping load. A simple method of tracking the maximum power points and forcing the system to operate close to these points is presented in this paper. The MC68HC908GP32 micro control unit (MCU) is employed to implement the proposed MPPT controller. Experimental results will also show the performances of the photovoltaic pumping system with the MPPT technique.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.13 no.4
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• pp.273-281
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• 2001

In this paper, we report the experimental and numerical results on spin-up flows in a rectangular container of the aspect ratio 2. The Ekman pumping models used in the numerical study are of 1st- and 2nd- order. We also investigate flows obtained without any pumping model. In the experiment, the classical PIV method is used. It is shown that the results given by the 1st-order and 2nd-order models are in good agreement with the experimental result, whereas the non-pumping model shows a significant discrepancy.

• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.161-163
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• 2006

This paper introduce the technology of peak demand reduction using automatic water tank pumping system on the apartment. That systems on the apartments installed water tank can control pumping(electricity) demand. Generally, system peak demand is occurred at the same time on workday and many water pumps consume electric power randomly. At this point, shift of operating time of water pump can reduce peak demand using automatic water tank pumping system. We were operating this system on some apartments for test of effect of peak demand reduction. and we represent result of demand shift. This result suggests that spread of the automatic water pumping system can contribute to reduce system peak demand and reduce system operation cost.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.4 no.4
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• pp.351-359
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• 1992

In order to improve the performance of heat exchanger, fluidized bed is often employed. The experiments are carried out in fluidized double pipe parallel flow heat exchanger in which finned tube is vertically immersed. And the heat transfer coefficients between the heated tube and fluidized bed of alumina beads(dp=0.41, 0.54, 0.65, 0.77mm) are calculated as a function of air fluidized velocity and pumping power. The effects of particle size, static bed height and pumping power on the heat transfer coefficients are investigated. And the heat transfer coefficients are compared with that of single phase forced convection heat exchanger. In particular, the heat transfer performance of each type heat exchanger is evaluated in relation to the pumping power.

• Journal of Korean Society on Water Environment
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• v.23 no.5
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• pp.628-635
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• 2007

As the hydrologic cycle is transformed by the expansion of impermeable area as a result of the urbanization, the function of an ecosystem is deteriorated by the transformed hydrologic cycle. In this study, a SWMM code was modified to have a groundwater pumping option about rivers-aquifer interaction to be possible. The modified SWMM was applied to continuous simulations of urban runoff from Hakuicheon watershed and it was used to analyse the effect of a groundwater pumping. The modified SWMM overcame the limitation of the ground subroutine that it only simulate groundwater inflow from ground to rivers. The result of continuous simulation of groundwater pumping is that surface runoff, groundwater runoff and groundwater level are well simulated, and Modified SWMM expressed groundwater runoff by negative number (-) when groundwater level is less than river stage.