• Journal of Life Science
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• v.18 no.10
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• pp.1426-1434
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• 2008

This study was conducted to investigate the effects of supplementation of synbiotics manufactured with anaerobic bacteria, yeast and mold on preservation of total mixed ration (TMR) by exposing days. Eight treatments were composed of untreated synbiotics(US), bacterial synbiotics (BS), yeasty synbiotics (YS), moldy synbiotics (MS), bacterial and mouldy synbiotics (BMS), yeasty and moldy synbiotics (YMS), bacterial and yeasty synbiotics (BYS), and bacterial, yeasty and moldy synbiotics (BYMS). After 7 days of anaerobic fermentation, fermented-TMRs were exposed to the air during 1, 3, 5, 7, 14 and 21 days. One hundred forty four (8 treatments${\times}$6 days${\times}$3 replications) fermented-TMRs were manufactured by vinyl bag ($43\;cm{\times}58\;cm$). Although no significant differences in the activities of carboxymethylcellulase, xylanase and amylase were observed among treatments, theirs acivities were seemed to increase by treatment of BYS or YMS containing yeast. Total bacterial and mold counts also decreased in the treatments containing yeast. Potential pathogenic bacteria were less detected in BYS and BMYS for E. coli, BMYS and YS for Salmonella, and BMS and BMYS for Shigella than those of the other treatments, MS was, however, contaminated easier than US by pathogenic bacteria. From above results, synbiotics containing facultative anaerobic yeast have effects for preservation of TMR fermented anaerobically. Particularly, BMYS treatment having good results in nutrient contents, dry matter loss and pathogenic bacteria amounts was a resonable synbiotics for preservation of the fermented-TMR.

• Journal of Bio-Environment Control
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• v.27 no.2
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• pp.103-110
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• 2018

This study was conducted to investigate the optimum irrigation method for propagation of cutting strawberry ($Fragaria{\times}ananassa$ Duch. cv. Maehyang) plantlet in summer season. The cutting strawberry plantlets were planted in 24-cell tray ($60{\times}34{\times}10cm$) filled with commercial mixed medium (Tosilee) and placed in semi closed-type small plastic tunnel. Each semi closed-type small plastic tunnel was treated as follows; control (non-treatment), over head irrigation (twice a day), capillary mats irrigation (twice a day), or fog irrigation (30 minutes turn on and 10 minutes off from 8:00 to 18:00). The strawberry plantlets were rooted during 8 days in the semi closed-type small plastic tunnel, and then plastic film was removed. Growth parameters, such as plant height, root length, number of primary roots, petiole length, leaf length, leaf width, crown diameter, SPAD, leaf area, fresh and dry weights of the shoot and root, were measured at 61 days after cutting. Relative humidity in tunnel was high in the order by fog irrigation, over head irrigation, capillary mats, and the control as 72.5, 56.3, 45.8, and 29% on average, respectively. However, the air temperature was similar in all treatments. On the 4 and 8 days, the rooting rate of strawberry plantlet was significantly higher in the over head irrigation and fog irrigation treatments. Plant height, petiole length, crown diameter, and leaf area were highest in the over head irrigation and fog irrigation treatments. In addition, fresh and dry weights of shoot were greater in over head irrigation and fog irrigation treatments than the others. Dry weight of root was differed significantly heaviest in the fog irrigation treatment. However, root length, no. of primary roots, SPAD value, and fresh weight of root were not significantly different in all treatments. These results indicated that growth and rooting for propagation of cutting strawberry plantlet 'Maehyang' were best achievement in the over head irrigation and fog irrigation treatments.

• Journal of the Korean Electrochemical Society
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• v.16 no.2
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• pp.59-64
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• 2013

Using $Na_2CO_3$ and $MeSO_4$ (Me = Ni, Co and Mn) as starting materials, the precursor of $[Ni_{0.6}Co_{0.2}Mn_{0.2}]CO_3$ has been synthesized by carbonate co-precipitation. The precursor was mixed with $Li_2CO_3$, and calcined at 750, 850, and$950^{\circ}C$ in air. Effect of calcinations temperature on characteristics of $Li[Ni_{0.6}Co_{0.2}Mn_{0.2}]O_2$ cathode materials was investigated. The structure and characteristics of $Li[Ni_{0.6}Co_{0.2}Mn_{0.2}]O_2$ were determined by X-ray diffraction (XRD), Scanning electron microscopy (SEM) and electrochemical measurements. The X-ray diffraction (XRD) results show that the intensity ratio of $I_{(003)}/I_{(104)}$ increased and the R-factor ratio decreased with the increase of calcinations temperature. And Scanning electron microscopy (SEM) result show that the primary particle size increased. Especially, the $Li[Ni_{0.6}Co_{0.2}Mn_{0.2}]O_2$ calcined at $950^{\circ}C$ for 24 H shows excellent electrochemical performances with reversible specific capacity of $165.3mAhg^{-1}$ [cut-off voltage 2.5~4.3 V, 0.1 C($17mAhg^{-1}$)] and good capacity retention of 95.4% after 50th charge/discharge cycles[cut-off voltage 2.5~4.3 V, 1 C($170mAhg^{-1}$)].

• The Transactions of the Korea Information Processing Society
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• v.1 no.3
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• pp.367-379
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• 1994

This paper describes scheduling algorithms of the UNIX operating system and shows an analytical approach to approximate the average conditional response time for a process in the UNIX operating system. The average conditional response time is the average time between the submittal of a process requiring a certain amount of the CPU time and the completion of the process. The process scheduling algorithms in thr UNIX system are based on the priority service disciplines. That is, the behavior of a process is governed by the UNIX process schuduling algorithms that (ⅰ) the time-shared computer usage is obtained by allotting each request a quantum until it completes its required CPU time, (ⅱ) the nonpreemptive switching in system mode and the preemptive switching in user mode are applied to determine the quantum, (ⅲ) the first-come-first-serve discipline is applied within the same priority level, and (ⅳ) after completing an allotted quantum the process is placed at the end of either the runnable queue corresponding to its priority or the disk queue where it sleeps. These process scheduling algorithms create the round-robin effect in user mode. Using the round-robin effect and the preemptive switching, we approximate a process delay in user mode. Using the nonpreemptive switching, we approximate a process delay in system mode. We also consider a process delay due to the disk input and output operations. The average conditional response time is then obtained by approximating the total process delay. The results show an excellent response time for the processes requiring system time at the expense of the processes requiring user time.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.1
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• pp.39-50
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• 2014

This paper reviews the results of recent observations in the Yeonsuri valley of Mt. Youngmun during springtime (March to May) in 2012. Automated weather stations were installed at twelve sites in the valley to measure temperature and 2, 3 dimensional wind. We examined temporal and spatial characteristics of temperatures and wind data. The Yeonsuri valley springtime average temperature lapse rate between the top and bottom of the entire period is $-0.44^{\circ}C/100$ m. It can be changed by the synoptic weather conditions, the lapse rates is greatest in order of clear days ($-0.48^{\circ}C/100$ m), rainy ($-0.41^{\circ}C/100$ m) and cloudy days ($-0.40^{\circ}C/100$ m). In the night, the temperature inversion layer (thermal belt) and the cold pool are formed within the valley. In addition, we measured temperature and wind distribution from the bottom to 3.5 m, the cold layers existed up to 1.5 m, which were affected by ground mixed layer. The results will provide useful guidance on agricultural practices as well as model simulations.

• Resources Recycling
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• v.9 no.4
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• pp.16-27
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• 2000

In order to produce raw material powder of advanced magnetic material by spray roasting process, newly modified spray roasting system was developed in this work. In this spray roasting system, raw material solution was effectively atomized and sprayed into the reaction furnace. Also, uniform temperature distribution inside reaction furnace made thermal decomposition process fully completed, and produced powder was effectively collected in cyclone and bag filter. This system equipped with apparatus which can purify hazard produced gas. In this study complex acid solution was prepared by dissolution of mill scale and ferro-Mn into the acid solution, and the pH of this complex acid solution was controlled about to 4. It was conformed that mill scale and ferro-Mn containing a lot of impurities such as $SiO_2$, P and Al could be used as raw material by reducing the impurities content of complex acid solution below 20 ppm. Complex oxide powder of Fe-Mn system was produced by spraying purified complex acid solution into the spray roaster through nozzle, and the variations of produced powder characters were studied by changing he reaction conditions such as reaction temperature, the injection velocity of solution and air, nozzle tip size and concentration of solution. The morphology of produced powder had spherical shape under the most experimental conditions, and concentration of solution. The morphology of produced powder has spherical shape under the most experimental conditions, and the composition and the particle size distribution were almost uniform, which tells the excellence of this spray roasting system. The grain size of most produced powder was below 100 nm. From the above results, it will be possible to produce ultra fine oxide powder from the chloride of Fe, Mn, Ni, Cu and rare earth by using this spray roasting system, and also to produce ultra fine pure metal powder by changing reaction atmosphere.