• 생물환경조절학회지
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• 제9권2호
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• pp.120-126
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• 2000

표고버섯(Lentinus edodes(Berk) Sing)의 품질은 환경조건에 매우 민감하고, 특히 생산기간중의 강우에 의한 수분의 영향이 큰 것으로 알려져 있다. 대부분의 경우, 표고버섯이 강우에 의하여 젖지 않도록 하기 위하여, 강우차단용 플라스틱 필름을 사용하여 측창 환기구 이외에는 모두 밀폐시킨 재배시설을 사용하고 있다. 그러나 이와 같이 천창이 없는 재배시설의 실내온도와 습도는 불량한 환기로 인하여 상승하게 되고, 결국 생산성 및 품질을 떨어뜨리게 된다. 본 연구에서는 모델을 이용하여 개선된 표고재배시설의 천창 면적과 차광율에 따른 환기율 및 실내온도 변화를 분석하였다. 차광율이 50%에서 90%로 증가할수록 온도는 약 2.5$^{\circ}C$ 이상의 차이를 나타냈으며 50%의 낮은 차광율에서 풍속의 영향이 크게 나타났다. 환기율은 풍속 1~2m.s-1 이상에서는 차광율에 관계없이 크게 증가하였다. 실외풍속이 0m.s-1에서 2m.s-1로 증가함에 따라 실내온도는 약 2$^{\circ}C$이상 하강하였다. 특히, 천창개도가 커질수록 온도가 하강하였지만 개도 50%이상에서는 큰 차이가 없었다. 차광율이 낮을수록 개도 증가가 온도하강에 미치는 영향이 뚜렸하였다. 풍속 및 차광율에 무관하게 천창면적과 측창면적이 거의 동일할 때, 높은 환기효율 및 온도하강 특성을 나타내었다.

• 한국음향학회지
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• 제39권1호
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• pp.57-63
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• 2020

바이노럴 비트는 양이에 도달한 소리의 주파수 차이로 유발된 주관적인 맥놀이 현상이다. 물리적으로 맥놀이의 세기는 주파수가 다른 두 신호의 크기에 영향을 받는다. 따라서 바이노럴 비트는 좌우 청력의 차이에 따라 영향을 받을 것으로 예상된다. 본 연구에서는 청력에 따른 효과를 평가하기 위해, 정상 청력을 가진 34명의 피실험자가 한 쪽 귀에 기준음[440 Hz, 50 dB Sound Pressure Level(SPL)], 반대 측 귀에 주파수가 다른 제시음(450 Hz)을 SPL을 감소하며 들을 때, 주관적으로 느끼는 바이노럴 비트 의 세기의 변화를 Semantic Differential Method(SDM) 이용하여 평가하도록 했다. 실험 결과 피실험자가 느끼는 바이노럴 비트의 세기는, 좌우 소리의 SPL 차이가 역치(2.2 dB)보다 크면, 좌우 소리의 SPL 차이가 증가함에 따라 지속적으로 유의하게 감소하는 것으로 나타났다. 이러한 결과는 바이노럴 비트 효과를 최대로 하기 위해 좌우 청력 차이를 적절한 범위(예. 2.2 dB) 이내로 유지하는 것이 필요하다는 것을 시사한다.

• 한국미생물·생명공학회지
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• 제46권1호
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• pp.29-39
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• 2018

Vibrio vulnificus needs various responsive mechanisms to survive and transmit successfully in alternative niches of human and marine environments, and to ensure the acquisition of steady energy supply to facilitate such unique life style. The bacterium had genetic constitution very different from that of Escherichia coli regarding metabolism of glycogen, a major energy reserve. V. vulnificus accumulated more glycogen than other bacteria and at various levels according to culture medium and carbon source supplied in excess. Glycogen was accumulated to the highest level in Luria-Bertani (3.08 mg/mg protein) and heart infusion (4.30 mg/mg protein) complex media supplemented with 1% (w/v) maltodextrin at 3 h into the stationary phase. Regarding effect of carbon source, more glycogen was accumulated when maltodextrin (2.34 mg/mg protein) was added than when glucose or maltose (0.78.1-14 mg/mg protein) was added as an excessive carbon source to M9 minimal medium, suggesting that maltodextrin metabolism might affect glycogen metabolism very closely. These results were supported by the analysis using the malP (encoding a maltodextrin phosphorylase) and malQ (encoding a 4-${\alpha}$-glucanotransferase) mutants, which accumulated much less glycogen than wild type when either glucose or maltodextrin was supplied as an excessive carbon source, but at different levels (3.1-80.3% of wild type glycogen). Therefore, multiple pathways for glycogen metabolism were likely to function in V. vulnificus and that responding to maltodextrin might be more efficient in synthesizing glycogen. All of the glycogen samples from 3 V. vulnificus strains under various conditions showed a narrow side chain length distribution with short chains (G4-G6) as major ones. Not only the comparatively large accumulation volume but also the structure of glycogen in V. vulnificus, compared to other bacteria, may explain durability of the bacterium in external environment.

• Journal of Oral Medicine and Pain
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• 제20권1호
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• pp.185-194
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• 1995

The purpose of this study was to estimate primary diagnosis, prediction of prognosis and recognition fo treatment progress for treatment of TMD patients through measuring the various ranges of mandibular movement in normal and TMDs patients using Mandibular Kinesiograph K-6 Diagnostic system. In normal groups, 20 adults were selected, who have normal or class I molar relationship, and have no symptoms on TMJ and masticatory muscles, and have restorations less than 3 surfaces on each tooth, and have no other prosthetic restoration. In Patients group, we selected 31 outpatients who were confirmed to TMDs with clinical examination and radiographic findings. The obtained results were as follows : 1. In maximal opening, patient group was showed the limitation of vertical movement range (P<0.01) and lager lateral deviation than in normal group (P<0.05). And actual dimensional displacement of opening was calculated larger in normal group (P<0.05). 2. In protrusive movement, patients group was showed the limitation of anteroposterior movement range (P<0.001) and larger deviation than in normal group (P<0.01). And actual 3 dimensional displacement of protrusion was calculated larger in normal group (P<0.001). 3. In lateral maximum excursion, compared with normal group patient group was no significant differences to affected side, but was showed the limitation of lateral movement to unaffected side (P<0.001). 4. There was no significant difference in movement velocity of opening and closing in both groups. 5. Mandibular movement from physiologic rest position to centric occlusion was moved more anteroposteriorly in patient group. 6. Mandibular movement from centric relation to centric occlusion was no significant difference in both groups.

• Design & Manufacturing
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• 제13권4호
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• pp.23-27
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• 2019

People's interest in the environmental problems of the Earth is growing as they come to the modern world, and research is being actively conducted on how to protect the environment. As a result, the automobile industry, one of the causes of environmental pollution, is also affected. Therefore, research is being conducted to improve the fuel economy and light weight of cars, development of pollution-free cars such as electric cars, and aluminium materials that are lighter than ordinary steel sheets and easier to recycle are gaining attention. In this experiment, the material was formed to form a form of aluminium and the material reduction rate of the side wall of the foam was tested according to the amount of side wall. The material used in the experiment was A3003-O, which is less plastic than normal steel plates, but has excellent corrosion resistance, plasticity and weldability compared to aluminium materials, but has poor tensile strength. For tensile testing, a certain array of Forming Shapes was molded and the height of the Forming was set to 5mm, and the height of the Forming was 4.7mm, indicating that the difference between the first 5mm Forming and the height was not large. In addition, the material reduction rate was tested by giving 15, 0, and -0.15 teas, respectively, and was found to be valuable as a product only for -0.15.

• 해양환경안전학회지
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• 제24권3호
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• pp.373-380
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• 2018

The small coastal vessel registered in Korea, small coastal vessels with a gross tonnage of 10 tons or less account for 94.6 % and among them, aged vessels over 16 years age indicate 40.6 %. In order to reduce GHG emissions from small coast vessels, discussions are underway to replace aging ships' propulsion units with eco - friendly propulsion facilities, and the electric propulsion ship is emerging as one of the measures. The electric propulsion system using the DFE rectifier, which was applied in the conventional large commercial vessel, was effective in reducing the harmonics and improving the DC output voltage of the DC link stage, but it occupied a large volume and caused an increase in the overall system price. Therefore, in this paper, we propose an electric propulsion system using AFE rectifier with a small volume of system that can be applied to a small coastal vessel. In order to analyze the effectiveness of the overall system, the load profile was applied to obtain accurate and rapid speed tracking performance of the propulsion motor affected by the speed load. In addition, the power factor and total harmonic distortion factor of the voltage and current on the improved power output side are derived through simulation.

• 한국환경농학회지
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• 제14권2호
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• pp.179-185
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• 1995

Carbofuran의 aminothio 유도체로서 국내에서 사용되고 있는 살충제들인 carbosulfan, furathiocarb 및 benfuracarb를 논 및 밭상태 수분조건별로 토양에 처리하고 토양중 분해양상 및 carbofuran 방출 특성을 조사하였다. 토양에 처리한 유도체들은 토양중에서 carbamoyl N-S간 결합의 붕괴에 따라 carbofuran을 빠른 속도로 방출하였다. 토앙중 분해반감기는 $23{\sim}68$시간 범위로서 유도체 측쇄구조 및 토양수분조건에 영향을 받는 것으로 나타났다. 토양 처리 5일후 유도체농약들의 carbofuran으로의 유효전환율은 $64{\sim}84%$ 범위였으며 유도체형태로의 처리는 carbofuran 직접처리에 비하여 토양중 carbofuran 전류수준의 급격한 상승을 완화, 직접살포에 따른 부작용을 경감시킬 수 있을 것으로 판단되었다.

• KSBB Journal
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• 제28권6호
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• pp.415-422
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• 2013

Gamma irradiation (${\gamma}IR$) is widely used for radiotherapy as a treatment of cancer cells although it has a risk to damage normal cells. Inflammation is regarded as one of side effects of ${\gamma}IR$ while the effect of low dose of ${\gamma}IR$ on inflammation has not been researched well. Here, we investigated the inflammatory responses of low dose of ${\gamma}IR$ on murine spleen cells. It was evaluated if ${\gamma}IR$ affected the mitogen-induced lymphocyte proliferation, the regulation of various inflammatory cytokines (IFN-${\gamma}$, IL-2, IL-17, IL-4, IL-10), and the involvement of Ikaros and MAPK/NF-${\kappa}B$ medicated mechanism. Exposure of $^{137}Cs-{\gamma}IR$ below 2 Gy decreased the lymphocytes proliferative response to mitogens (LPS, ConA) except at the lowest dose, 0.05 Gy. IL-17, IL-2 and IL-4 mRNA increased at 0.5 and 2 Gy, but not altered at 0.05 Gy. IL-10, anti-inflammatory cytokine, increased only at 0.05 Gy. In regard to intracellular signaling, p-JNK, p-p38 and p-$I{\kappa}B{\alpha}$ were not changed, whereas the activation of ERK and Ikaros increased at the lowest dose. These results suggest that exposure of ${\gamma}IR$ less than 0.5 Gy (or below 0.05 Gy) has beneficial effects as a radiation hormesis on immune function.

• Archives of Reconstructive Microsurgery
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• 제13권2호
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• pp.117-122
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• 2004

Purpose : The aim of this study was to evaluate the efficacy of arterialized venous flap in finger flexion contracture correction. Materials and methods : From 2002 to 2004, we have performed 10 arteriaized venous flap for treatment of severe flexion contracture in digit. The duration of flexion contracture was from 1 year to 50 years. The cause of contracture were bum scar(7 cases), postoperative contracture(2 cases) and other(l case). We evaluated the survival of flap, flap size, recovery of flexion contracture and subjective satisfaction. Results : All arterialized venous flap survived. The marginal minimal skin necrosis developed in 2 cases. The flap size was average $5.2{\times}3.5cm$. The recovery of flexion contracture was 87% compared with non affected side. 9 patients(90%) satisfied the results of operation. Conclusion : Arterialized venous flap is one of the useful procedure in treatment of finger flexion contracture because it has many advantages such as thin and good quality, variable length of pedicle, preservation of major vascular pedicle, less operation time and in addition possibility of various modifications.

• International Journal of Aeronautical and Space Sciences
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• 제3권1호
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• pp.95-104
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• 2002

Numerical solution of the full Navier-Stokes equation as well as the energy equation has been obtained for the unsteady natural convection in a rectangular enclosure. One side wall was maintained at very high temperature simulating fires. Especially the effect of surface radiation was taken into account. While the enclosed air was assumed to be transparent, the internal walls directly interacted one another through the surface radiation. Due to a significant temperature difference in the flow field, the equation of state was used instead of the Boussinesq approximation. It was found that the rapid heating of the adiabatic ceiling and floor by the incoming radiation from the hot wall made the evolution at thermo-fluid field highly unstable in the initial period. Therefore, the secondary cells brought about at the floor region greatly affected the heat transfer mechanism inside the enclosure. The heat transfer rate was augmented by the radiation, resulting in requiring less time for the flow to reach the steady state. At the steady state neglecting radiation two internal hydraulic jumps were clearly observed in upper/left as well as in lower/right comer. However, the hydraulic jump in the lower/right comer could not be observed for the case including radiation due to its high momentum flow over the bottom wall. Radiation resulted in a faster establishment of the steady state phenomena.