• Journal of Energy Engineering
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• v.28 no.1
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• pp.30-36
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• 2019

The military has developed and operated a variety of military vehicles. Among them, medium tactical vehicles are developed as vehicles suitable for transporting troops, replacing existing military trucks, which have a significant impact on infantry forces' combat capability. Applying technology to increase fuel efficiency to these critical weapons systems, medium tactical vehicles, increases the distance range, which can reduce effective operational performance and oil costs. In this study, a measure was taken to improve the distance range of Medium Tactical Vehicles by applying an oil temperature control strategy to increase fuel efficiency.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.6
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• pp.743-750
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• 2013

In this study, the carbonized aggregate of light weight and high mechanical strength using sewage sludge was evaluated with changing carbonation variables of temperature, detention time and feed condition. Porosity and mechanical strength was simultaneously increased according to increase of carbonization temperature unexpectedly. Carbonization detention time above 1 hour nearly affect on the porosity, but mainly on mechanical strength of the carbonized aggregate in case of clay addition. On $900^{\circ}C$, porosity and mechanical strength was increased rapidly, but above $1000^{\circ}C$, porosity began to decrease. Clay addition was very effective on increase of mechanical strength following much loss in porosity. The carbonized aggregate manufactured at $900^{\circ}C$ adding 30 % clay in sewage sludge was higher a little in porosity and 3 times in mechanical strength than those at $700^{\circ}C$ not adding clay. Consequently, in manufacturing the carbonized aggregate having simultaneously high porosity and mechanical strength, it is desirable to have operational condition of $900{\sim}1000^{\circ}C$ temperature and 1 hour time, and clay addition within 30 % for further higher mechanical strength.

• Safety and Health at Work
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• v.9 no.1
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• pp.42-52
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• 2018

Background: Maintenance operations on-board ships are highly demanding. Maintenance operations are intensive activities requiring high man-machine interactions in challenging and evolving conditions. The evolving conditions are weather conditions, workplace temperature, ship motion, noise and vibration, and workload and stress. For example, extreme weather condition affects seafarers' performance, increasing the chances of error, and, consequently, can cause injuries or fatalities to personnel. An effective human error probability model is required to better manage maintenance on-board ships. The developed model would assist in developing and maintaining effective risk management protocols. Thus, the objective of this study is to develop a human error probability model considering various internal and external factors affecting seafarers' performance. Methods: The human error probability model is developed using probability theory applied to Bayesian network. The model is tested using the data received through the developed questionnaire survey of >200 experienced seafarers with >5 years of experience. The model developed in this study is used to find out the reliability of human performance on particular maintenance activities. Results: The developed methodology is tested on the maintenance of marine engine's cooling water pump for engine department and anchor windlass for deck department. In the considered case studies, human error probabilities are estimated in various scenarios and the results are compared between the scenarios and the different seafarer categories. The results of the case studies for both departments are also compared. Conclusion: The developed model is effective in assessing human error probabilities. These probabilities would get dynamically updated as and when new information is available on changes in either internal (i.e., training, experience, and fatigue) or external (i.e., environmental and operational conditions such as weather conditions, workplace temperature, ship motion, noise and vibration, and workload and stress) factors.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.8 no.1
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• pp.40-46
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• 2009

This paper presents a self-sustaining system, and an effective method in enhancing overall energy efficiency. The proposed system consists of the two major nodes: a slave node, which contains the environment information (e.g., temperature, humidity, etc.); and a master node, which communicates with the slave nodes, and transmit the slave node's information to users. All slave nodes are under control of the master node. Each slave node uses two power sources: the piezoelectric power generator (PPG); and the continuous wave from the master node. The paper highlights the basic operational principle, each node's specifications, and experimental data for performance verification. The two nodes successfully communicate each other in a range of 3.3m (maximal range), where the user's computer is wired the master node.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.1
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• pp.37-40
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• 2003

The antibacterial action of violet pigment, a mixture of violacein and deoxyviolacein, isolated from phychrotrophic bacterium RT102 strain was examined, and the operational conditions for the effective production of violet pigment were studied. The antibacterial activity of the violet pigment was confirmed for several bacteria such as Bacillus licheniformis, Bacillus subtilis, Bacillus megaterium, Staphylococcus aureus, and Pseudomonas aeruginosa, and the high concentration of violet pigment, above about 15mg/L, caused not only growth inhibition but also death of cells. The growth properties of RT102 strain were clarified under various incubation conditions such as pH, temperature, and dissolved oxygen concentration. The maximum violet pigment concentration, i.e. 3.7 g/L, and the maximum productivity of violet pigment, i.e. 0.12 g .L$\^$-1/H$\^$-1/, were obtained in a batch culture of pH 6, 20$^{\circ}C$, and 1 mg/L of dissolved oxygen concentration.

• Journal of Energy Engineering
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• v.24 no.2
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• pp.51-54
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• 2015

The mesoporous metal organic framework structure of Ni-BTC was successfully synthesized in a low temperature and short operation time via hydrothermal synthesis process. Such operational route virtuously consumed less electrical and thermal energy. It proved time saving along with acceptable product yield (38%). The product was characterized through FESEM, FT-IR, XRD and $N_2$ gas adsorption measurement. Hightemperature stability of synthesized MOF was gauged by diffraction indexing of XRD patterns of as synthesized and heat treated samples of MOFs. The mathematically calculated particle size of Ni-BTC was found to be 42nm.

• Transactions of Materials Processing
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• v.6 no.6
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• pp.482-488
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• 1997

New carbon equivalent equation for the better prediction for the better prediction of roll force in a continuous hot strip mill has been formulated by applying a neural network method. In predicting roll force of steel strip, carbon equivalent equation which normalize the effects of various alloying elements by a carbon equivalent content is very critical for the accurate prediction of roll force. To overcome the complex relationships between alloying elements and operational variables such as temperature, strain, strain rate and so forth, a neural network method which is effective for multi-variable analysis was adopted in the present work as a tool to determine a proper carbon equivalent equation. The application of newly formulated carbon equivalent equation has increased prediction accuracy of roll force significantly and the effectiveness of neural network method is well confirmed in this study.

• Food Science of Animal Resources
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• v.44 no.5
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• pp.967-987
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• 2024

Recently, as the concept of pet food that satisfies both nutritional needs and the five senses has evolved, so too has the demand for effective pet food non-thermal sterilization methods. Prominent non-thermal technologies include high-pressure processing, plasma, and radiation, which are favored for their ability to preserve nutrients, avoid residues, and minimize compositional changes, thereby maintaining quality and sensory properties. However, to assess their effectiveness on pet food, it is essential to optimize operational parameters such as pressure levels, plasma intensity, radiation dosage, and temperature. Further studies are needed to evaluate microbial sterilization efficacy and sensory attributes. This exploration is expected to lay the groundwork for preventing zoonotic diseases and improving the production of high-quality pet food.

• Nuclear Engineering and Technology
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• v.41 no.3
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• pp.287-294
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• 2009

Due to thermal hydraulics phenomena, such as thermal stratification, various events occur to the parts of a nuclear power plant during their lifetimes: e.g. cracked and dislocated pipes and thermally fatigued, bent, and damaged supports. Due to the operational characteristics of the parts of the steam generator feedwater inlet horizontal pipe, thermal stratification takes place particularly frequently. However, the thermal stress due to thermal stratification at the steam generator feedwater inlet horizontal pipe was not reflected in the design stage of old plants(Kori Unit No.1, 2, 3 and 4, Yeonggwang Unit No. 1 and 2, and Uljin Unit No. 1 and 2; referred to as old-style power plants hereinafter). Accordingly, a verification experiment was performed for thermal stratification in the horizontal inlet nozzle steam generator of old-style plants. If thermal stratification occurred in the horizontal pipe of an old-style power plant, numerical analysis of the temperature distribution of the pipes and fluids was conducted. The temperature distributions were compared at the curved part of the pipe and the horizontal pipe before and after the installation of the improved thermal sleeves designed to alleviate thermal stress due to thermal stratification. The thermal stress reduction measure was proven effective at the steam generator inlet horizontal pipe and the curved part of the pipe.

• Smart Structures and Systems
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• v.15 no.3
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• pp.665-682
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• 2015

Structural identification or St-Id is 'the parametric correlation of structural response characteristics predicted by a mathematical model with analogous characteristics derived from experimental measurements'. This paper describes a St-Id exercise on Humber Bridge that adopted a novel two-stage approach to first calibrate and then validate a mathematical model. This model was then used to predict effects of wind and temperature loads on global static deformation that would be practically impossible to observe. The first stage of the process was an ambient vibration survey in 2008 that used operational modal analysis to estimate a set of modes classified as vertical, torsional or lateral. In the more recent second stage a finite element model (FEM) was developed with an appropriate level of refinement to provide a corresponding set of modal properties. A series of manual adjustments to modal parameters such as cable tension and bearing stiffness resulted in a FEM that produced excellent correspondence for vertical and torsional modes, along with correspondence for the lower frequency lateral modes. In the third stage traffic, wind and temperature data along with deformation measurements from a sparse structural health monitoring system installed in 2011 were compared with equivalent predictions from the partially validated FEM. The match of static response between FEM and SHM data proved good enough for the FEM to be used to predict the un-measurable global deformed shape of the bridge due to vehicle and temperature effects but the FEM had limited capability to reproduce static effects of wind. In addition the FEM was used to show internal forces due to a heavy vehicle to to estimate the worst-case bearing movements under extreme combinations of wind, traffic and temperature loads. The paper shows that in this case, but with limitations, such a two-stage FEM calibration/validation process can be an effective tool for performance prognosis.