• Journal of Bio-Environment Control
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• v.25 no.2
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• pp.123-132
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• 2016

The importance of energy saving technology for managing greenhouse was recently highlighted. For practical use of energy in greenhouse, it is necessary to simulate energy flow precisely and estimate heating/cooling loads of greenhouse. So the main purpose of this study was to develope and to validate greenhouse energy model and to estimate annual/maximum energy loads using Building Energy Simulation (BES). Field experiments were carried out in a multi-span plastic-film greenhouse in Jeju Island ($33.2^{\circ}N$, $126.3^{\circ}E$) for 2 months. To develop energy model of the greenhouse, a set of sensors was used to measure the greenhouse microclimate such as air temperature, humidity, leaf temperature, solar radiation, carbon dioxide concentration and so on. Moreover, characteristic length of plant leaf, leaf area index and diffuse non-interceptance were utilized to calculate sensible and latent heat exchange of plant. The internal temperature of greenhouse was compared to validate the greenhouse energy model. Developed model provided a good estimation for the internal temperature throughout the experiments period (coefficients of determination > 0.85, index of agreement > 0.92). After the model validation, we used last 10 years weather data to calculate energy loads of greenhouse according to growth stage of greenhouse crop. The tendency of heating/cooling loads change was depends on external weather condition and optimal temperature for growing crops at each stage. In addition, maximum heating/cooling loads of reference greenhouse were estimated to 644,014 and $756,456kJ{\cdot}hr^{-1}$, respectively.

• Korean Journal of Materials Research
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• v.21 no.10
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• pp.573-579
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• 2011

Highly textured Ag, Al and Al:Si back reflectors for flexible n-i-p silicon thin-film solar cells were prepared on 100-${\mu}m$-thick stainless steel substrates by DC magnetron sputtering and the influence of their surface textures on the light-scattering properties were investigated. The surface texture of the metal back reflectors was influenced by the increased grain size and by the bimodal distribution that arose due to the abnormal grain growth at elevated deposition temperatures. This can be explained by the structure zone model (SZM). With an increase in the deposition temperatures from room temperature to $500^{\circ}C$, the surface roughness of the Al:Si films increased from 11 nm to 95 nm, whereas that of the pure Ag films increased from 6 nm to 47 nm at the same deposition temperature. Although Al:Si back reflectors with larger surface feature dimensions than pure Ag can be fabricated at lower deposition temperatures due to the lower melting point and the Si impurity drag effect, they show poor total and diffuse reflectance, resulting from the low reflectivity and reflection loss on the textured surface. For a further improvement of the light-trapping efficiency in solar cells, a new type of back reflector consisting of Ag/Al:Si bilayer is suggested. The surface morphology and reflectance of this reflector are closely dependent on the Al:Si bottom layer and the Ag top layer. The relationship between the surface topography and the light-scattering properties of the bilayer back reflectors is also reported in this paper.

• Food Science and Preservation
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• v.16 no.2
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• pp.166-171
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• 2009

The effects of vacuum precooling(VP) on the shelf-life of polyethylene film(PE) packaged King oyster mushrooms(Pleurotus eryngii) during storage at $-1^{\circ}C$ were investigated. VP was conducted below $0^{\circ}C$ in a $-1^{\circ}C$ cold chamber of 40 minutes, and mushrooms were stored for 30 days in batches of 1kg. The weight loss of the VP-treated mushroom was slightly lower than that of control. The $O_2$ concentrations of VP-treated mushroos, within 4 days of storage, were 2.44-14.50 %/kg-package/hr, thus higher than control values(2.01-8.19%/kg-package/hr). $CO_2$ generation of VP-treated mushrooms, again within 4 days of storage, was 0.47%/kg-package/hr, thus lower than that of controls(0.58%/kg-package/hr). The $CO_2/O_2$ ratio peaked on day 4 of storage in the control group, tbut no such peak was observed in VP-treated mushrooms. In the VP-treated fungi, lightness was higher, and redness and yellowness lower, than in controls, at all storage times.. In VP-treated mushrooms, strength, hardness and chewiness were significantly higher than in controls, but there were no significant differemces in springiness or cohesiveness. Softening and breakdown of under-cap wrinkles were observed in control mushrooms stored for 30 days, but occurred to a lesser extent in VP-treated fungi. Stipe reticulum tissue vessels in the 30 day-stored VP-treated mushrooms were relatively well-defined and clear, but were softer and diffuse in the control fungi. The results thus confirmed that VP after harvest enhanced mushroom shelf-life and PE packaging prolonged storage time. The data will have industrial applications.

• Tuberculosis and Respiratory Diseases
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• v.43 no.4
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• pp.637-644
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• 1996

Interstitial pneumonitis associated with interferon alpha therapy for chronic hepatitis C was first describe6 in 1994 by Kazoo et al In Japan. The mechanism of interstitial pneumonitis developed by interferon alpha was still unknown but immunologic, allergic of direct lung toxicity were suggested. We experienced a case of interstitial pneumonitis developed during interferon alpha therapy for chronic hepatitis C in a 52-year-old male patient. He was treated with 6 million units of interferon alpha intramuscularly 3 times per week for 4 weeks and noted progressive dyspnea and cough. These symptoms were subsided after 6 weeks' discontinuation of interferon alpha therapy. And so, he was retreated with 3 million units of interferon alpha 3 times per week for 8 weeks and felt dyspnea again. He was admitted to our hospital for further evaluation of progressive dyspnea. Arterial blood gas(ABG) values were $PaO_2$ 90.7 mmHg and $PaCO_2$ 31.9 mmHg, and antinuclear antibody(ANA) was negative. A chest X-ray film revealed diffuse reticulo-nodular shadows in bilateral lung fields, suggesting a diagnosis of interstitial pneumonitis. A marked increase in lymphocyte count and suppressor T cell were observed in bronchoalveolar lavage(BAL) fluid. Lymphocyte stimulation test with interferon alpha was positive. Interstitial pneumonitis was confirmed by transbronchial lung biopsy. After discontinuation of interferon alpha, we gave oral steroid in the condition that clinical symptoms were being improved gradually.

• Journal of the Korean Orthopaedic Association
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• v.53 no.6
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• pp.498-504
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• 2018

Purpose: To evaluate the clinical and radiological outcomes, and the complications of unicompartmental knee arthroplasty (UKA) using a fixed bearing prosthesis after 5-year follow-up. Materials and Methods: Twenty-six knees (25 patients) that underwent fixed bearing UKA between May 2003 and August 2011 were included. The subjects were 3 males (3 knees) and 22 females (23 knees), and the average age was 63.5 years. The preoperative diagnosis was osteoarthritis (23 knees) and osteonecrosis (3 knees). The mean follow-up duration was 67 months (from 60 to 149 months). The clinical evaluation included pre- and postoperative American knee society knee and function score, and range of motion. The radiology evaluation included standing antero-posterior, lateral view, and fluoroscopic film to analyze the postoperative alignment and osteolysis. Results: The mean American Knee Society knee score and function score were improved from 42.0 and 57.5 to 87.9 and 85.0, respectively (p<0.001). The mean preoperative and postoperative range of motion was $132.9^{\circ}$ and $132.5^{\circ}$, respectively. The mean femorotibial angle were varus $0.5^{\circ}$ preoperatively and valgus $2.2^{\circ}$ postoperatively. A radiolucent line was observed in 2 knees; one knee had a stable implant, while in the other knee, patellofemoral arthritis was identified during UKA. Diffuse pain of the knee joint with tenderness of the medial joint line was identified at the follow-up, so conversion to total knee arthroplasty was recommended. No other complications, such as osteolysis, infections, postoperative stiffness, and dislocation, were encountered. Conclusion: The midterm results of fixed bearing UKA were clinically and radiologically satisfactory.