• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.1
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• pp.107-114
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• 2021

In this paper, a planar transistor oscillator for X-band using a newly proposed L-shaped monopole slot resonator is proposed. For planar design, an L-shaped monopole slot with an open-end is used as a resonator for a transistor oscillator. As a result of the simulated design of the resonator in three stages, a high Q value of 1169.84 and a high insertion loss of 49.934 dB were identified. The results of the final design and manufactured oscillator measurements confirmed that the oscillation output is greater than 7 dBm and has good phase noise characteristics of -58 dBc/Hz at 100 kHz offset. The proposed oscillator is planar and has the advantage of being directly applicable to microwave integrated circuit technology. It also has the advantage of being able to reduce its size as it can only be implemented in microstrip form without additional devices such as metal cavities and tuning screws in 3D structures, as in the case of a DRO (dielectric resonance oscillator).

• The korean journal of orthodontics
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• v.38 no.5
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• pp.337-346
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• 2008

Objective: The purpose of this study was to determine whether an exogenous electric current to the alveolar bone surrounding a tooth being orthodontically treated can enhance tooth movement in human and to verify the effect of electric currents on tooth movement in a clinical aspect. Methods: This study was performed on 7 female orthodontic patients. The electric appliance was set in the maxilla to provide a direct electric current of $20{\mu}A$. The maxillary canine on one side was assigned as the experimental side, and the other as control. The experimental canine was provided with orthodontic force and electric current. The control side was given orthodontic force only. Electrical current was applied to experimental canines for 5 hours a day. The amount of canine movement was measured with an electronic caliper every week. Results: The amount of orthodontic tooth movement in the experimental side during 4 weeks was greater by 30% compared to that of the control side. The amount of increase in tooth movement in the experimental side was statistically significant. The amount of tooth movement in the experimental side during the first two weeks was !Bleater than that in the following two weeks. The amount of weekly tooth movement in the control side was decreased gradually. Conclusions: These results suggested that the exogenous electric current from the miniature electric device might accelerate orthodontic tooth movement by one third and have the potential to reduce orthodontic treatment duration.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.1
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• pp.91-105
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• 2020

This study is the basic study for improving the range of influence and potency of mixing bars in the chamber of Shield TBM. Currently, there are many studies on disk cutters, cutter bits and segments in the study of the domestic Shield TBM. However, studies that mix soil and rocks that come from the membrane during the Shield TBM excavation and scatter them with screw conveyors are not as good as those abroad. In this study, the existing Shield TBM Chamber was manufactured as a miniature and the experiment. Inside the chamber, different sizes (4 mm, 6 mm, 8 mm, 10 mm) and colors (black, white, red, and blue) were used to form layers. This experiment was carried out by different shapes and sizes of RPM and mixing bars. In addition, the difference between a miniature model and a reclining one was checked to determine the effect of the direction of gravity on the mixing efficiency. This was done in the same way for all other conditions other than differences in the direction of gravity. Through this experiment, we identified the orientation of the chamber model, the size and shape of the mixing bar inside, and the mixing effect and torque depending on RPM. A comparative review of the mixing effect and torque confirmed that the shape and size of the mixing bar affect the mixing of samples, and that the direction of gravity affects torque.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.5
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• pp.571-577
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• 2012

In this study, a small movable batch treatment system for dredging soil deposited in a rain water tube is proposed; further, a vacuum silo sorting separation device with a vacuum silo, first-stage sorting separator, and conveyor is designed. The vacuum silo sorting separation device also consists of a storage tank, transferring screw, vacuum gate, screen bar, screen bar cleaner, and vacuum discharging device. In view of the fact that the flow of drawn air in the storage tank is a major factor influencing the sorting separation performance, the optimum shape of the tank is determined by CFD flow analysis. In addition, by using CAE structure analysis, the safety of a storage tank made of boards is examined. The specifications of the vacuum silo sorting separation device are determined by conducting mechanical and dynamic simulations of the driving mechanism of the vacuum silo sorting separation device through 3D-CAD modeling. Following this study, we will design a drum-screen-type second sorter, a decanter-type dehydration device, and waste water tank and pump as a secondary device. Further, on the basis of this design, we will construct a prototype model and carry out a field test.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.355-361
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• 2002

본 연구에서는 원적외선.열풍 복합건조특성을 구명하기 위하여 건조용량 150-500kg이고, 승강기, 상.하부스크류, 건조실, 템퍼링실, 송풍기 및 가열장치로 구성된 시뮬레이터를 제작하여 건조특성시험을 실시하였다. 그 결과를 요약하면 다음과 같다. 가. 열풍온도에 따른 곡온변화를 시험한 결과 열풍온도 45$^{\circ}C$일 때 곡온 32-33$^{\circ}C$를 유지하였으며, 48, 51$^{\circ}C$일 때는 곡온이 35$^{\circ}C$가 넘어서는 현상을 나타났다. 건조중 곡온이 35$^{\circ}C$를 넘어서게 되면 동할미 발생량이 많아지고 품질저하가 급격히 일어난다. 나. 템퍼링실의 온도편차가 2,5$^{\circ}C$ 정도로 고른 온도분포를 나타내었고, 버너 입구쪽과 템퍼링실 중앙지점에서 온도가 약간 높게 나타났으며, 원적외선방사체 표면온도분포는 열풍온도가 45$^{\circ}C$일 때 평균 17$0^{\circ}C$를 유지하였고, 48$^{\circ}C$, 51$^{\circ}C$일 때 각각 22$0^{\circ}C$, 23$0^{\circ}C$에서 유지하는 것으로 나타났다. 다. 원적외선방사체 길이방향으로 온도편차는 버너를 기준으로 해서 버너쪽에서 멀수록 온도가 높았고, 중간, 근거리 순으로 나타났다. 버너의 원거리쪽에서 온도가 높게 나타난 것은 원적외선방사체를 통과하는 열풍이 빠져나가도록 되어있는 열풍 유동관이 버너 원거리에 위치하고 있어 버너에 불꽃이 점화되면서 열풍이 방사체 끝쪽으로 일시 머물렀다가 배출되기 때문으로 판단된다. 라. 건조기의 송풍량을 요인으로 하여 건조속도와 건조에너지를 비교한 결과 송풍량이 30cmm일 때가 25cmm에서보다 약 33%의 건조속도가 증가되어 송풍량이 많을수록 건조속도가 빨라졌으나, 건조에너지는 1,391kcal/kg.water로 나타나 약 4.2%정도가 더 소요 되었다. 곡물순환속도를 요인으로 하여 비교 시험한 결과 곡물순환속도가 33kg/min일때가 26kg/min보다 약 25%의 건조속도가 증가되어 곡물의 순환속도가 빠를수록 건조속도가 빨라졌으며, 건조에너지도 1,334kcal/kg.water로 비슷하게 소요되었다. 마. 시험구와 대비구의 건감률은 시험구에서 1.08~1.36w.b./h로 나타나 대비구보다 약 9.9~18.3%가 높게 나타났고, 건조에너지는 10.2~14.6%가 절감되었다. 발아율은 열풍온도가 낮을수록 높게 나타났고 시험구가 대비구보다 발아율이 낮게 나타났으며, 동할률 증가량도 원적외선.열풍 복합건조방법이 높게 나타나 이것은 곡물 표면에 원적외선 방사에의한 복사열이 전달되어 열장해를 받았기 때문으로 판단되며, 금후 더 연구하여 적정 열풍온도 및 방사체 크기를 구명해야 할 것이다.

• Journal of Korea Entertainment Industry Association
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• v.13 no.3
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• pp.27-41
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• 2019

The study tested the old wines of Château Latour 1953 and tried to analyze the differences from the old wines. Even if not the great vintage, the quality change of old wine gives a new flavor, so it requires analysis results from empirical concepts, decanting, and testing. Based on the analysis results, the government wanted to re-evaluate the old wine and give consumers joy and implications for the wine. The wine to be studied is Château Latour 1953 and is an old wine from the French province of Pauillac. Wine blending is known to be 75% of cabernet sauvignon, 20% of melot, 4% of cabernet franc and 1% of petit verdot. The alcohol level is 13% and the test date is July 2-7, 2018(decanting period 5.4 days/15:00 p.m. on July 7). The testing site was a wine cafe in Daegu City, and the tester consisted of one FICB Korean grand commander and one KOV Finland commander and selected Japchae of Korean food as a mariage. The ullage of Chateau Latour 1953 was 3.0cm and was set up for one month for testing. Decanting time was applied to the calculation formula 2018(current year)-1953(vintage year)/12=5.4 days, which was investigated in this study. Aroma smelled of cork, old grapes, tobacco, leaves and leather, the bouquet was identified in five stages, and the testing was analyzed in seven stages.

• The Journal of the Convergence on Culture Technology
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• v.10 no.5
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• pp.453-458
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• 2024

If you are unable to get comfortable sleep to maintain and recover your health, it will cause a lot of disruption to your daily life. Among the intraoral devices used to resolve snoring, obstructive sleep apnea, bruxism, teeth clenching, and mouth breathing, which interfere with a comfortable sleep, devices that stabilize the lower jaw by moving it forward are a treatment that replaces surgical therapy and positive airway pressure. It is showing effect. During use of the device, a force is generated that causes the lower jaw to return to its original position, so a device that fixes it with screws, rubber bands, etc. is used. To see the effect of the device, you must bite your upper and lower teeth. In order to eliminate the inconvenience of having to stay closed while sleeping, the device is manufactured only in the upper jaw and creates a vertical guideway in the lingual embarasure of the lower jaw in the shape of a key & key way structure, allowing twisting movements and allowing forward and lateral movements. It is about the development of a device that has a blocking function that allows the mouth to be opened while wearing the device and has a function that solves sleep apnea by inducing airway expansion during sleep.