• Journal of Drive and Control
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• v.20 no.2
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• pp.40-46
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• 2023

Fresh corn, one of the main food crops, must be harvested by hand. A harvest mechanization technology is required. In this study, a tractor-attached harvester was designed and manufactured to sequentially perform stem reaping, fresh corn detaching, and collecting. The(harvester was designed so that the main device could operate through a hydraulic pump and a generator could be operated through the tractor's PTO. Factor tests were conducted according to cultivars (Ilmichal, Super sweet corn) and working speed (0.12 m/s, 0.17, 0.22). After the factor test, detached corns ratio, collected corns ratio, and damaged corns ratio were analyzed and harvest performance was evaluated. Harvesting performance was good for super sweet corn. Considering operation efficiency, 0.22 m/s was judged to be an appropriate working speed. It was found that it took two hours to work an area of 10 a.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.4_2
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• pp.617-626
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• 2020

The drilling mud is essentially used in oil and gas development. There are several roles of using the drilling mud, such as cleaning the bottomhole, cooling and lubricating the drill bit and string, transporting the cuttings to the surface, keeping and adjusting the wellbore pressure, and preventing the collapse of the wellbore. The fragments from rocks and micro-sized bubbles generated by the high pressure are mixed in the drilling mud. The systems to separate those mixtures and to keep the uniformly maintained quality of drilling mud are required. In this study, the simulation is conducted to verify the performance of the mud tank's agitation capacity. The primary role of the mud tank is the mixing of mud at the surface with controlling the mud condition. The container type is chosen as a mud tank pursuing efficient transport and better management of equipment. The single- and two-phase simulations about the agitation in the mud tank are performed to analyze and identify the inner flow behavior. The convergence of results is obtained for the vertical- and axis-direction velocity vector fields based on the grid-dependency tests. The mixing time analysis depending on the multiphase flow conditions indicates that the utilization of a two-stepped impeller with a smaller size provides less time for mixing. This study's results are expected to be utilized as the preliminary data to develop the mixing and integrating equipment of the onshore drilling mud system.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.675-681
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• 1994

[ $F_0$ ]-values of the canned tuna in cottonseed oil (CTCO) were investigated under different sterilizing conditions to optimize the energy consumption and microbiological safety. The $F_0$-values were measured using a microcomputer based technique. The exact cold point was not the volumetric center of the cans, and it was located in the center of meat mass in can which had ca. $6\%$ of head space. Location of the test cans in retort showed no remarkable influence on the $F_0$-values when the cans were jumble loaded. The process time before sterilization should be shortened as much as possible to prevent the contamination of microorganisms. Thermophilic spore forming bacteria found from raw and precooked tuna were Bacillus subtilis, Bacillus cereus and Bacillus pasteurii, and the most heat resistant was Bacillus subtilis. The rational $F_0$-value for the CTCO obtained from the preservation test was regarded as 6min.

• Journal of Food Hygiene and Safety
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• v.34 no.2
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• pp.135-139
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• 2019

The objective of this research was to compare loop-mediated isothermal amplification (LAMP) with real-time polymerase chain reaction (PCR) for the rapid detection of pathogens in foods. In this study, the limits of detection (LODs) for Salmonella Typhimurium, Listeria monocytogenes, and Cronobacter sakazakii were evaluated in various foods. Among 11 samples tested for S. Typhimurium, LAMP and real-time PCR had the same LODs in beef and duck meat whereas real-time PCR was more sensitive than the LAMP in 8 samples. However, S. Typhimurium in chocolate samples was not detected by real-time PCR. The sensitivity of real-time PCR was high in all samples inoculated with L. monocytogenes and C. sakazakii whereas LAMP was more sensitive than real-time PCR in oil-rich foods. Therefore, LAMP can be shown as an easrer, more convenient method, as well as effective analytical method for testing difficult samples when employed in PCR.