• Korean Journal of Head & Neck Oncology
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• v.34 no.1
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• pp.15-19
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• 2018

Background and Objectives: Thunderbeat (TB) and Harmonic scalpel (HS) have been applied to variable head and neck surgery, which are useful for both coagulation and cutting of tissues. However, there have been no comparative studies covering the usefulness of these energy devices in surgery for major salivary gland. In this study, we analyzed the surgical outcomes of two devices in surgery for parotidectomy and submandibular gland (SMG) resection. Materials and Methods: A retrospective chart review of 90 patients including two groups (HS group, n=45 versus TB group, n=45) of patients matched for their patient factors was conducted. Clinicopathologic factors of the patients and surgical outcomes such as the operation time, intraoperative bleeding, amount and duration of drain, hospital stay and complications were compared between two groups. Results: There were no significant difference between two groups regarding the clinicopathologic factors and short-term surgical outcomes. Conclusion: Thunderbeat and HS are both effective and safe for parotidectomy and SMG resection in variable benign disease of major salivary gland.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1252-1258
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• 2018

Objective: This study was carried out to determine the effects of cumin essential oil on the silage fermentation, aerobic stability and in vitro digestibility of alfalfa silages. Methods: Alfalfa was harvested at early bloom (5th cutting) stage in October and wilted for about 3 hours. The research was carried out at three groups which were the control group where no additive control was done (CON), cumin essential oil (CMN3) with 300 mg/kg and CMN5 with 500 mg/kg cumin essential oil addition. Alfalfa was ensiled in plastic bags. The packages were stored at $8^{\circ}C{\pm}2^{\circ}C$ under laboratory conditions. All groups were sampled for physical, chemical and microbiological analysis 120th day after ensiling. At the end of the ensiling period, all silages were subjected to an aerobic stability test for 7 days. In addition, enzimatic solubility of organic matter (ESOM), metabolizable energy (ME), and relative feed value (RFV) of these silages were determined. Results: pH level decreased in the cumin groups compared to CON (p<0.05), thus inhibiting proteolytic enzymes from breaking down proteins into ammonia. In addition, it increased ESOM amount, and concordantly provided an increase of ME contents. Similarly, dry matter intake and RFV ratio increased. After opening the silage, it kept its aerobic stability for three days. Conclusion: Cumin essential oil improved fermentation, and affected chemical and microbiological characteristics of silages. Especially the addition of 300 mg/kg cumin provided cell wall fractionation through stimulating the activities of enzymes responsible. It also increased the number and activity of lactic acid bacteria (LAB) through providing a development of LAB.

• Korean Journal of Optics and Photonics
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• v.3 no.4
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• pp.227-233
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• 1992

The simulation code was developed for the development of the split-disk geometry glass amplifier, which could design the laser apparatus and analyze the properties of the laser system. The flashlamp emission energy at the short wavelength region must be reduced, while maintaining a current density between 2000 and 4000 A/$\textrm{cm}^{2}$, in order to reduce the thermal loading in the laser glass and to raise the coupling efficiency between the emission spectrum of the flashlamps and the absorption spectrum of the laser glass. By cutting the laser glass into three equal pieces, the temperature rise in the laser glass dropped by 70% due to the efficient removal of the heat in the laser glass. It was found that the $Nd^{3+}$ doping rate of each laser glass should be properly selected and the optimum value of the product of the absorption coefficient $\alpha$ and the thickness d of the laser glass is about 0.26 in the split-disk geometry.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.6
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• pp.375-381
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• 2019

Structural health monitoring to determine structural conditions at an early stage and to efficiently manage the energy requirements of buildings using systems that collects relevant data, is under active investigation. Structural monitoring requires cutting-edge technology in which construction, sensing, and ICT technologies are combined. However, the scope of application is limited because expensive sensors and specialized technical skills are often required. In this study, a Raspberry Pi module, one of the most widely used single board computers, a Lora module that is capable of long-distance communication at low power, and a high-performance accelerometer are used to construct a wireless edge computing system that can monitor building response over an extended time period. In addition, the Raspberry Pi module utilizes an edge computing algorithm, and only meaningful data is obtained from the vast amount of acceleration data acquired in real-time. The raw data acquired using Wi-Fi communication are compared to the Laura data to evaluate the accuracy of the data obtained using the system.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.496-501
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• 1995

Experiments were carried out to find out the optimal condition of SCP produced by Cellulomonas sp. KL-6 and to evaluate nutritional value for the protein of this organism Intracellular- and extracellular proteins produced by this strain were estimated to be nearly maximum, $266\;{\mu}g/m{\ell}\;and\;37\;{\mu}g/m{\ell}$, in the medium containing 0.001% of thiamin after 5 days cultivation. When used rice straw as carbon source for the cell growth of this organism after crusing them by cutting mill, and treating them with 1.0% of NaOH and 10.0% of $NH_4OH\;at\;80^{\circ}C$ for 30 minutes and neutralizing continuatively them with 85% of $H_3PO_4$, SCP production rates were very increased to $1.63\;g/{\ell}$ (NaOH) and $1.47\;g/{\ell}$ (NH4OH), respectively than $0.5\;g/{\ell}$ produced in untreated rice straw. We compared their amino acids patterns with that of FAO provisional patterns. Amino acids content of strain KL-6 was excellents. However. when intended these cell mass to use in practical animal feeding test it would be advisable that destruction or lysis of cell wall should be done.

• Resources Recycling
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• v.23 no.4
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• pp.30-36
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• 2014

300,000 tons of waste tires are annually being produced with development of the automotive industry in Korea. Landfill and incineration treatment system are causing the economic problem through secondary environmental pollution and waste. Therefore, as one of the ways to take advantage of this, Thermo-Plastic Vulcanized (TPV) composite was prepared by the ground waste tire and plastic powders. The waste tire powder was gained by mechanical fracturing through crushers. The waste tire powder was ground by a shear crushing method and a 2-stage disk mill method instead of cutting crushing one. The waste tire powder of 50 mesh was mixed with Polypropylene(PP) in various proportions. TPVs were prepared by an extrusion, and tensile and impact tests were performed. In addition, the same experiments were repeated in 40, 80, 140 mesh conditions in order to observe size effect of waste tire powders.

• Journal of the Korean Institute of Gas
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• v.15 no.3
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• pp.47-52
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• 2011

The purpose of this paper analyzes and studies to seek the failure examples of electronic control actuators for engine in liquified petroleum gas vehicle. The first, it was verified phenomenon for intial starting damage and no-acceleration of engine because of occasionally fuel feeding interception by clogged of emergency cutting solenoid valve filter. The second, the contact resistance produced in the connecting part of engine control relay because of no fully surface contacting by processes and assembly badness. It was displayed phenomenon of re-starting badness. The actuator that idle speed control system was sticked inside because of intake-air decreasing by carbon deposit. As a result, it was verified the phenomenon of disharmony that repeated up and down the engine revolution.

• Geomechanics and Engineering
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• v.18 no.5
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• pp.535-543
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• 2019

Building on/with expansive soils with no treatment brings complications. Compacted expansive soils specifically fall short in satisfying the minimum requirements for transport embankment infrastructures, requiring the adoption of hauled virgin mineral aggregates or a sustainable alternative. Use of hauled aggregates comes at a high carbon and economical cost. On average, every 9m high embankment built with quarried/hauled soils cost $12600MJ.m^{-2}$ Embodied Energy (EE). A prospect of using mixed cutting-arising expansive soils with industrial/domestic wastes can reduce the carbon cost and ease the pressure on landfills. The widespread use of recycled materials has been extensively limited due to concerns over their long-term performance, generally low shear strength and stiffness. In this contribution, hydromechanical properties of a waste tyre sand-sized rubber (a mixture of polybutadiene, polyisoprene, elastomers, and styrene-butadiene) and expansive silt is studied, allowing the short- and long-term behaviour of optimum compacted composites to be better established. The inclusion of tyre shred substantially decreased the swelling potential/pressure and modestly lowered the compression index. Silt-Tyre powder replacement lowered the bulk density, allowing construction of lighter reinforced earth structures. The shear strength and stiffness decreased on addition of tyre powder, yet the contribution of matric suction to the shear strength remained constant for tyre shred contents up to 20%. Reinforced soils adopted a ductile post-peak plastic behaviour with enhanced failure strain, offering the opportunity to build more flexible subgrades as recommended for expansive soils. Residual water content and tyre shred content are directly correlated; tyre-reinforced silt showed a greater capacity of water storage (than natural silts) and hence a sustainable solution to waterlogging and surficial flooding particularly in urban settings. Crushed fine tyre shred mixed with expansive silts/sands at 15 to 20 wt% appear to offer the maximum reduction in swelling-shrinking properties at minimum cracking, strength loss and enhanced compressibility expenses.

• Korean Journal of Materials Research
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• v.29 no.11
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• pp.684-689
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• 2019

Single crystals, which have complexed composition, are fabricated by solid state grain growth. However, it is hard to achieve stable properties in a single crystal due to trapped pores. Aerosol deposition (AD) is suitable for fabrication of single crystals with stable properties because this process can make a high density coating layer. Because of their unique features (nano sized grains, stress inner site), it is hard to fabricate single crystals, and so studies of grain growth behavior of AD film are essential. In this study, a $BaTiO_3$ coating layer with ${\sim}9{\mu}m$ thickness is fabricated using an aerosol deposition method on (100) and (110) cut $SrTiO_3$ single crystal substrates, which are adopted as seeds for grain growth. Each specimen is heat-treated at various conditions (900, 1,100, and $1,300^{\circ}C$ for 5 h). $BaTiO_3$ layer shows different growth behavior and X-ray diffraction depending on cutting direction of $SrTiO_3$ seed. Rectangular pillars at $SrTiO_3$ (100) and laminating thin plates at $SrTiO_3$ (110), respectively, are observed.

• Animal Bioscience
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• v.35 no.8
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• pp.1162-1173
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• 2022

Objective: This study aimed to investigate the fermentation profiles, bacterial community and predicted metabolic characteristics of Sudangrass (Sorghum sudanense Stapf.) during ensiling. Methods: First-cutting Sudangrass was harvested at the vegetative stage and ensiled in laboratory-scale silos (1 L capacity). Triplicate silos were sampled after 1, 3, 7, 15, 30, and 60 days of ensiling, respectively. The bacterial communities on day 3 and 60 were assessed through high-throughput sequencing technology, and 16S rRNA-gene predicted functional profiles were analyzed according to the Kyoto encyclopedia of genes and genomes using Tax4Fun. Results: The Sudangrass silages showed good fermentation quality, indicated by higher lactic acid contents, and lower pH, butyric acid and ammonia nitrogen contents. The dominant genus Lactococcus on day 3 was replaced by Lactobacillus on day 60. The metabolism of amino acid, energy, cofactors and vitamins was restricted, and metabolism of nucleotide and carbohydrate was promoted after ensiling. The 1-phosphofructokinase and pyruvate kinase of bacterial community seemed to play important roles in stimulating the lactic acid fermentation, and the promotion of arginine deiminase could help lactic acid bacteria to tolerate the acidic environment. Conclusion: High-throughput sequencing technology combined with 16S rRNA gene-predicted functional analyses revealed the differences during the early and late stages of Sudangrass ensiling not only for distinct bacterial community but also for specific functional metabolites. The results could provide a comprehensive insight into bacterial community and metabolic characteristics to further improve the silage quality.