• Geomechanics and Engineering
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• v.35 no.6
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• pp.571-580
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• 2023

During EPB shield tunnelling, construction speed and safety are severely affected by spewing. In this study, a theoretical seepage model is established to capture of the effects of screw conveyor geometry and turbulent flow on spewing. Experimental test results are used to verify the proposed theoretical seepage model. It is found that the seepage is greatly affected by the length of screw conveyor and soil permeability. The proposed model can increase the screw conveyor length and reduce soil discharge sections simultaneously, the permeability of treated muck thus decreases by one order of magnitude. By using the proposed theoretical seepage model, the criterion of critical soil permeability used to identify spewing is proposed. When the water head applied at tunnel face reaches 40 m and 50 m, the critical permeability coefficients of treated muck should be less than 10^-5 m/s and 10^-6 m/s to avoid spewing. For a given permeability coefficient of soil, the water flow rate is overestimated if structural characteristics of screw conveyor is not considered. Consequently, the occurrence of spewing is greatly overestimated, which increases construction cost substantially.

• The Journal of Korean Medical History
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• v.15 no.1
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• pp.147-182
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• 2002

By studing the congestion theory of Choo Dan-kyei mentioned in "DongEuiBoGam", I have reached following conclusions. 1. Dan-kyei's congestion theory influenced greatly on "DongEuiBoGam". The congestion theory of "DongEuiBoGam" is built up with several theories centering round on Dan-kyei's theory and Huh-Jun's own opinion in addition. 2. Dan-kyei's congestion theory has given theoretical foundation to the classification and diagnosis of congestion reported in "DongEuiBoGam"-Congestion Chapter. 3. Dan-kyei's congestion theory offers many examples of symptoms reported in "DongEuiBoGam"-Congestion Chapter. It's shown well through outer symptoms, several congestion disease, congestion mass, and "congestion never sudden death", etc. 4. Dan-kyei's congestion theory has influenced greatly on treatment of congestion reported in "DongEuiBoGam"-Congestion Chapter, and it's well shown through spewing method, grand method in congestion treatment and common medicine of congestion, etc. 5. Dan-kyei's congestion theory offers variety of treating methods to symptoms caused by congestion reported in "DongEuiBoGam". It's shown variously through upper stomachache, stomachache, back pain, side pain, "San", joint pain, Summer disease, internal injury, cough and morning sickness, etc.. 6. Dan-kyei's congestion theory has factors that could be operated to common diseases of mordern people. They can be classified as food congestion, alcohol congestion, obstruction congestion and Qi congestion, and they are clinically very efficient.

• International Journal of Industrial Entomology and Biomaterials
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• v.34 no.2
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• pp.17-22
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• 2017

Cooked mature silkworms have received increasing attention as a new source of income for sericultural farms. Quality improvement of these worms as the end-product requires prevention of the following: inclusion of unfertilized silkworm eggs, mixing with impurities, producing undercooked or overcooked mature larvae, and mixing spewed silk substance. Preventing unfertilized eggs and impurities and reducing undercooked or overcooked mature larvae can be achieved by sericultural farms. However, the prevention of spewed silk substance requires the development of new techniques. This study developed new techniques for optimum cold storage temperature, soaking, and hydro-thermal treatment to minimize the spewing of mature larvae prior to steaming: when larvae mature after 7 days on the $5^{th}$ instar, they should be soaked in water at room temperature of $25^{\circ}C$ immediately upon collection and stored at $8^{\circ}C$ for less than 3 days. They should be soaked in boiling water for approximately 10 s immediately before steaming to kill the larvae and cooked with steam. This method allows for the production of high-quality mature larvae without spewed silk substance. These new techniques will considerably improve the production of well-cooked quality mature larvae by minimizing silk substance spewed out from the larvae.

• Geomechanics and Engineering
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• v.34 no.6
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• pp.637-648
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• 2023

When an earth pressure balance (EPB) shield machine bores a tunnel in gravelly sand stratum, the excavated natural soil is normally transformed using foam and water to reduce cutter wear and the risk of direct muck squeezing out of the screw conveyor (i.e., muck spewing). Understanding the undrained shear behavior of conditioned soils under pressure is a potential perspective for optimizing the earth pressure balance shield tunnelling strategies. Owing to the unconventional properties of conditioned soil, a pressurized vane shear apparatus was utilized to investigate the undrained shear behavior of foam-conditioned gravelly sands under normal pressure. The results showed that the shear stress-displacement curves exhibited strain-softening behavior only when the initial void ratio (e₀) of the foam-conditioned sand was less than the maximum void ratio (e_max) of the unconditioned sand. The peak and residual strength increased with an increase in normal pressure and a decrease in foam injection ratio. A unique relation between the void ratio and the shear strength in the residual stage was observed in the e-ln(τ) space. When e₀ was greater than e_max, the fluid-like specimens had quite low strengths. Besides, the stick-slip behavior, characterized by the variation coefficient of measured shear stress in the residual stage, was more evident under lower pressure but it appeared to be independent of the foam injection. A comparison between the results of pressurized vane shear tests and those of slump tests indicated that the slump test has its limitations to characterize the chamber muck fluidity and build the optimal conditioning parameters.

• Tuberculosis and Respiratory Diseases
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• v.49 no.2
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• pp.246-252
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• 2000

Lymphangioleiomyomatosis(LAM) is a rare disease of unknown etiology that occurs mainly in woman in her reproductive age. We recently experienced two cases of bilateral diffuse cystic lesion of the lung on chest X-ray and HRCT. The first case, a 26-year-old female, who had been diagnosed with tuberous sclerosis by the presence of clinical manifestation such as mental retardation, bilateral renal angiomyolipoma, adenoma sebaceum and generalized seizure, was admitted due to a recently developed hemoptysis. Chest PA showed diffuse ground-glass opacity with radiolucent cystic lesions of various sizes on both lung fields. HRCT showed innumerable small cystic lesions with suspicious diffuse ground-glass opacity on both lung fields The second case, a 30-year-old fema1e was admitted due to dyspnea and spewing of blood-tinged sputum for 2 weeks, shortly after delivery. Chest PA showed diffuse reticular and ground-glass opacities on both lung field. HRCT showed multiple well-defined and relatively uniform size air cysts with a uniform wall thickness on entire both lung fields, with small amount of right pleural effusion. By thoracoscopic lung biopsy she was diagnosed with pulmonary lymphangioleiomyomatosis. We report these cases with a brief review of the literatures.