• Korean Journal of Veterinary Research
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• v.42 no.4
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• pp.485-493
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• 2002

The purpose of this study was to develope a computer program to help with gross diagnosis of protein-energy balance and feeding management practice and with the prediction about the risk possibility of productive disease such as reproductive and metabolic disorders by evaluating fat, protein, and milk urea nitrogen (MUN) from individual cow milk in dairy herd Somatic cell counts also represent the condition of udder health. The principal flow charts of this program was to check on herd management, sampling the composite milk, analysis the milk composition, conversion of data from milking equipment to program, input and analysis of data in program, and report. This program is compatible with window 95/98 system. The major analytical elements of this program were presented as; the profile of herd lactation curve analysis of the test-day milk production level, the distribution of somatic cell count, the fat to protein ratio to evaluate body energy balance, and the interpretation of dietary protein-energy balance by milk protein and MUN contents for individual cows. This program using milk fat, protein, MUN, and somatic cell counts will serve as a monitoring tool for the protein-energy balance and the feeding management practice, and for distribution of mastitis in individual cows. It will also be used to manage the nutritional and reproductive disorders and mastitis at the farm level.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.5
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• pp.465-477
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• 2023

In proton exchange membrane fuel cell (PEMFC), proper thermal management of the stack and moisture generation by electrochemical reactions significantly affect fuel cell performance. In this study, the PEMFC dynamic characteristic model was developed through Simcenter AMESim, a development program. In addition, the developed model aims to understand the thermal resin balance of the stack and performance characteristics for input loads. The developed model applies the thermal management model of the stack and the moisture content and permeability model to simulate voltage loss and stack thermal behavior precisely. This study extended the C based AMESet (adaptive modeling environment submodeling tool) to simulate electrochemical reactions inside the stack. Fuel cell model of AMESet was liberalized with AMESim and then integrated with the balance of plant (BOP) model and analyzed. And It is intended to be used in component design through BOP analysis. The resistance loss of the stack and thermal behavior characteristics were predicted, and the impact of stack performance and efficiency was evaluated.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.12
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• pp.1395-1401
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• 2014

In an effort to develop and implement an inertial balance with high performance, the response characteristics of a load cell, which are some of the critical parameters for optimal system design, were evaluated using a sample object of approximately 100 g under microgravity conditions. To this end, a 15-m drop-tower was used to produce microgravity conditions, and the response characteristics of the load cell were investigated in terms of the variations in the magnitude of the deceleration of the sample object, noting that the mass of a living animal should be determined in microgravity. An analysis of the ratio of the inertial forces clearly demonstrated that the average velocity of a load cell plate should be higher than 0.5 m/s to meet the design requirements.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.93-100
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• 2014

Background: Curcumin has has been reported to exert anti-inflammatory, anti-oxidation and anti-angiogenic activity in various types of cancer. It has also been shown to induce apoptosis in leukemia cells. We aimed to unravel the role of the redox pathway in Curcumin mediated apoptosis with a panel of human leukemic cells. Materials and Methods: In this study in vitro cytotoxicity of Curcumin was measured by MTT assay and apoptotic effects were assessed by annexin V/PI, DAPI staining, cell cycle analysis, measurement of caspase activity and PARP cleavage. Effects of Curcumin on intracellular redox balance were assessed using fluorescent probes like $H_2DCFDA$, JC1 and an ApoGSH Glutathione Detection Kit respectively. Results: Curcumin showed differential anti-proliferative and apoptotic effects on different human leukemic cell lines in contrast to minimal effects on normal cells. Curcumin induced apoptosis was associated with the generation of intracellular ROS, loss of mitochondrial membrane potential, intracellular GSH depletion, caspase activation. Conclusions: As Curcumin induces programmed cell death specifically in leukemic cells it holds a great promise as a future therapeutic agent in the treatment of leukemia.

• Proceedings of the KIEE Conference
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• 2005.04a
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• pp.277-279
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• 2005

The imbalance of energy demand and supply caused by rapid industrialization around the world and the associated environmental issues require and alternative energy source with possible renewable fuels. Political instability and depletion of cruel oils are other factors that cause fluctuation of oil price. Securing a new alternative energy source for the next century became an urgent issue that our nation is confronting with. As a matter of fact, the fuel cell technology can be widely used as next generation energy regardless of regions and climate. Specially, the ability of expansion and quick installation enable one to apply it for distributed power, where the technology is already gaining remarkable attentions for the application. Particularly, leading industrialized nations are focusing on the PEM fuel dell with anticipation that this technology will find their place of applications in the vehicles and homes. In this study, demonstrate the multi physics modeling of a proton exchange membrane(PEM) fuel cell with interdigitated flow field design. The model uses current balances, mass balance(Maxwell-Stefan diffusion for reactant, water and nitrogen gas) and momentum balance(gas flow) to simulate the PEM fuel cell behavior.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.2
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• pp.91-101
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• 2012

A 200 W portable polymer electrolyte membrane fuel cell (PEMFC) system is developed. The PEMFC system consists of an air-cooled fuel cell stack module, a fuel supply subsystem, a power management subsystem, and a control electronics subsystem. The control logic is designed for the stable system operation. The system-level performance evaluation discloses that the present PEMFC system provides a rated power output of 200.5 W at 13.4 V with the maximum balance-of-plant (BOP) efficiency of 72%, and maximum system efficiency based on lower heating value (LHV) is 37% at 120.7 W system power output.

• Transactions of the Korean hydrogen and new energy society
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• v.23 no.4
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• pp.300-309
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• 2012

Long endurance is a key issue in the application of unmanned aerial vehicles. This study presents feasibility test results when fuel cell system as an alternative to the conventional engine is applied for the power of the UAV after the 150W fuel cell system is developed and packaged to the 1/4 scale super cub airplane. Fuel cell system is operated by dead-end method in the anode part and periodically purged to remove the water droplet in flow field during the operation. Oxygen in the air is supplied to the stack by the two air blowers. And fuel cell stack is water cooled by cooling circuit to dissipate the heat generated during the fuel cell operation. Weight balance is considered to integrate the stack and balance of plant (BOP) in package layout. In flight performance test, we demonstrated 4 times standalone take-off and landing. In the laboratory test simulating the flight condition to quantify the energy flow, the system is analyzed in detail. Sankey diagram shows that electric efficiency of the fuel cell system is 39.2%, heat loss 50.1%, parasitic loss 8.96%, and unreacted purged gas 1.67%, respectively compared to the total hydrogen input energy. Feasibility test results show that fuel cell system is high efficient and appropriate for the power of UAV.

• Korean Chemical Engineering Research
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• v.46 no.5
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• pp.915-921
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• 2008

In most PEM fuel cell research, effects of cell geometry, physical properties of component such as membrane, carbon cloth, catalyst, etc. and water transport phenomena are key issues. The scope of these research was limited to single cell and stack except BOP(Balance of plant) of fuel cell. The research fouced on the fuel cell system usually neglect to consider detailed transport phenomena in the cell. The research of the fuel cell system was interested in a system performance and system dynamics. In this paper, the effect of the anode recirculation is calculated using the 2D steady-state model. For this work, 2D steady-state modeling and experiments are performed. For convenience of modifying of model equation, not commercial pakage but the in-house algorithm was used in simulation. For an vehicle industry, the analysis of the anode recirculation system helps the optimization of operating condition of the fuel cell.

• Proceedings of the KIPE Conference
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• 2003.07a
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• pp.189-192
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• 2003

Electrical power in satellite system should persistently satisfy specified power requirement even though that happen the failure of solar array string or battery cell during the mission operation. In this study, the solar array and battery of GEO Communication Satellite with 3kW capacity are designed, and energy balance analysis according to power operation mode are performed to meet specified power capacity at the transfer orbit

• Journal of the Korean Electrochemical Society
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• v.2 no.2
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• pp.75-80
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• 1999

Li-ion cells employ lithium transtion metal oxide as the cathode material and carbon as anode material. To manufacture Li-ion cell with higher capacity and better cycle life, the utilization of electrode materials should be as high as possible without lithium deposition onto the carbon surface during charging. A careful design of cell balance between cathode and anode materials as well as a proper charge method is a key factor to design Li-ion cell with long cycle life. In this study, we investigated the effect of cathode/anode weight ratio on the performance of $LiCoO_2/MPCF$ cell. First we evaluated the charge-discharge behaviours of half-cells. And cylindrical Li-ion cells were fabricated using graphitized MPCF anode and $LiCoO_2$ cathode. The voltage profiles for each half-cell in $LiCoO_2/MPCF$ cell were measured by using lithium metal as a reference electrode. Also, we evaluated the cyclic performance of $LiCoO_2/MPCF$ cells according to weight ratio. From the result of experiment $LiCoO_2$ cathode utilization was independent of weight ratio, but MPCF anode utilization was dependant on weight ratio. Also, the optimal weight ratio of $LiCoO_2/MPCF$ cell was found to be $2.0\~2.2$.