• Advances in aircraft and spacecraft science
• /
• v.4 no.6
• /
• pp.701-709
• /
• 2017

One of the components that used in the satellite thermal control subsystem is the Mechanically Pumped Fluid Loop (MPFL) system; this system mostly used in geosynchronous orbit (GEO) satellites, and can transfer heat from a hot point to a cold point using the fluid which circulated in a closed loop. Heat radiates to the deep space at the cold plate to cool down the fluid temperature. In this research, the radiative heatexchanger (RHX) for a MPFL system is optimized. The genetic algorithm has been used for minimizing the total mass and pressure drop by considering a constant transferred heat rate at the heat exchanger. The optimization has been done in two cases. In case I, two parameters are considered as a goal function, so optimization is performed using NSGA-II method. Results of optimization are shown in the pareto diagram. In case II, the diameter of pipe is considered constant, so the optimized value for distances of the parallel pipes is obtained by using the genetic algorithm, in which the system has the least total mass. Results show that in the RHX, by increasing the pipe diameter, pressure drop decreases and total mass increases. Also by considering a constant value for pipe diameter, an optimum distance between pipes and pipe length are obtained in which the system has a minimum mass.

• Structural Engineering and Mechanics
• /
• v.40 no.5
• /
• pp.637-654
• /
• 2011

The present paper studies the variation of the natural frequencies and mode shapes of rectangular plates carrying a three degree-of-freedom spring-mass system (subsystem), when the subsystem changes (stiffness, mass, moment of inertia, location). An analytical approach based on Lagrange multipliers as well as a finite element formulation are employed and compared. Numerically reliable results are presented for the first time, illustrating the convenience of using the present analytical method which requires only the solution of a linear eigenvalue problem. Results obtained through the variation of the mass, stiffness and moment of inertia of the 3-DOF system can be understood under the effective mass concept or Rayleigh's statement. The analysis of frequency values of the whole system, when the 3-DOF system approaches or moves away from the center, shows that the variations depend on each particular mode of vibration. When the 3-DOF system is placed in the center of the plate, "new" modes are found to be a combination of the subsystem's modes (two rotations, traslation) and the bare plate's modes that possess the same symmetry. This situation no longer exists as the 3-DOF system moves away from the center of the plate, since different bare plate's modes enable distinct motions of the 3-DOF system contributing differently to the "new' modes as its location is modified. Also the natural frequencies of the compound system are nearly uncoupled have been calculated by means of a first order eigenvalue perturbation analysis.

• Tuberculosis and Respiratory Diseases
• /
• v.75 no.3
• /
• pp.116-119
• /
• 2013

Sarcoidosis, a systemic granulomatous disease of unknown etiology. The presentation of sarcoidal granuloma in neck nodes without typical manifestations of systemic sarcoidosis is difficult to diagnose. We describe the case of a 37-year-old woman with an increasing mass on the right side of neck. The excisional biopsy from the neck mass showed noncaseating epithelioid cell granuloma of the lymph nodes. No evidence of mycobacterial or fungal infection was noted. Thoracic evaluations did not show enlargement of mediastinal lymph nodes or parenchymal abnormalities. Immunohistochemistry showed abundant expression of tumor necrosis factor-${\alpha}$ in the granuloma. However, transforming growth factor-${\beta}$ was not expressed, although interleukin-$1{\beta}$ was focally expressed. These immunohistochemical findings supported characterization of the granuloma and the diagnosis of sarcoidosis. Sarcoidosis can present with cervical lymph node enlargement without mediastinal or lung abnormality. Immunohistochemistry may support the diagnosis of sarcoidosis and characterization of granuloma.

• Journal of Gastric Cancer
• /
• v.12 no.2
• /
• pp.108-112
• /
• 2012

Purpose: Since a patient's obesity can affect the mortality and morbidity of the surgery, less drastic surgeries may have a major benefit for obese individuals. This study evaluated the feasibility of performing a totally laparoscopic distal gastrectomy, with intracorporeal anastomosis, in obese patients suffering from gastric cancer. Materials and Methods: This was a retrospective analysis of the 138 patients, who underwent a totally laparoscopic distal gastrectomy from April 2005 to March 2009, at the National Kyushu Cancer Center. The body mass index of 20 patients was ${\geq}25$, and in 118 patients, it was <25 kg/$m^2$. Results: The mean values of body mass index in the 2 groups were $27.3{\pm}2.2$ and $21.4{\pm}2.3$. Hypertension was significantly more frequent in the obese patients than in the non-obese patients. The intraoperative blood loss, duration of surgery, post-operative complication rate, post-operative hospital stay, and a number of retrieved lymph nodes were not significantly different between the two groups. Conclusions: Intracorporeal anastomosis seemed to have a benefit for obese individuals. Totally laparoscopic gastrectomy is, therefore, considered to be a safe and an effective modality for obese patients.

• Mass Spectrometry Letters
• /
• v.5 no.1
• /
• pp.16-23
• /
• 2014

Liquid chromatography based mass spectrometry (LC-MS) is a key technology for analyzing highly complex and dynamic proteome samples. With highly accurate and sensitive LC-MS analysis of complex proteome samples, efficient data processing is another critical issue to obtain more information from LC-MS data. A typical proteomic data processing starts with protein database search engine which assigns peptide sequences to MS/MS spectra and finds proteins. Although several search engines, such as SEQUEST and MASCOT, have been widely used, there is no unique standard way to interpret MS/MS spectra of peptides. Each search engine has pros and cons depending on types of mass spectrometers and physicochemical properties of peptides. In this study, we describe a novel data process pipeline which identifies more peptides and proteins by correcting precursor ion mass numbers and unifying multi search engines results. The pipeline utilizes two open-source software, iPE-MMR for mass number correction, and iProphet to combine several search results. The integrated pipeline identified 25% more proteins in mouse epididymal adipose tissue compared with the conventional method. Also the pipeline was validated using control and colitis induced colon tissue. The results of the present study shows that the integrated pipeline can efficiently identify increased number of proteins compared to the conventional method which can be a breakthrough in identification of a potential biomarker candidate.

• Journal of Korean Society of Environmental Engineers
• /
• v.33 no.5
• /
• pp.325-331
• /
• 2011

A numerical analysis of reactive flow in a MILD(Moderate and Intense Low oxygen Dilution) combustor is accomplished to elucidate the characteristics of combustion phenomena in the furnace with the change of fuel and air nozzle position and air mass flow rate. For the case with the fuel nozzle located near center position of combustor, the reaction zone started at the fuel nozzle and had inclined shape toward combustor wall when the air mass flow rate was relatively smaller. On the other hand, the end of reaction zone moved toward center of combustor from combustor wall when the air flow rate was relatively larger. For the case with the air nozzle located near center position of combustor, the reaction zone started at the fuel nozzle and had inclined shape toward combustor wall when the air mass flow rate was relatively small, which was similar as the previous case with smaller air mass flow rate. On the other hand, the end of reaction zone moved toward combustor wall when the air flow rate was relatively larger. The maximum temperature increased as the air mass flow rate increasing for both cases, and the concentration of thermal NOx increased also from the previous reason of temperature characteristics. The concentration of NOx for the case with the air nozzle located near center position of combustor was considerably smaller than that for the case with the fuel nozzle located near center position of combustor. From the present study, the case with the air nozzle located near center position of combustor and theoretical air flow rate was the most effective condition for the NOx reduction and perfect combustion.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
• /
• 2004.05a
• /
• pp.103-108
• /
• 2004

• Earthquakes and Structures
• /
• v.25 no.6
• /
• pp.417-427
• /
• 2023

If the center of mass and center of stiffness or strength of a structure plan do not coincide, the structure is considered asymmetric. During an earthquake, in addition to lateral vibration, the structure experiences torsional vibration as well. Lateraltorsional coupling in asymmetric structures in the plan will increase lateral displacement at the ends of the structure plan and, as a result, uneven deformation demand in seismically resistant frames. The demand for displacement in resistant frames depends on the magnitude of transitional displacement to rotational displacement in the plan and the correlation between these two. With regard to the inability to eliminate the asymmetrical condition due to various reasons, such as architectural issues, this study has attempted to use supplemental viscous dampers to decrease the correlation between lateral and torsional acceleration or displacement in the plan. This results in an almost even demand for lateral deformation and acceleration of seismic resistant frames. On this basis, using the concept of Torsional Balance, adequate distribution of viscous dampers for the decrease of this correlation was determined by transferring the "Empirical Center of Balance" (ECB) to the geometrical center of the structure plan and thus obtaining an equal mean square value of displacement and acceleration of the plan edges. This study analyzed stiff and flexible torsional structures with one-way and two-way mass asymmetry in the Opensees software. By implementing the Particle Swarm Optimization (PSO) algorithm, the optimum formation of dampers for controlling lateral displacement and acceleration is determined. The results indicate that with the appropriate distribution of viscous dampers, not only does the lateral displacement and acceleration of structure edges decrease but the lateral displacement or acceleration of the structure edges also become equal. It is also observed that the optimized center of viscous dampers for control of displacement and acceleration of structure depends on the amount of mass eccentricity, the ratio of uncoupled torsional-to-lateral frequency, and the amount of supplemental damping ratio. Accordingly, distributions of viscous dampers in the structure plan are presented to control the structure's torsion based on the parameters mentioned.

• Journal of Microbiology and Biotechnology
• /
• v.8 no.3
• /
• pp.203-207
• /
• 1998

Fed-batch fermentations with different feeding media were carried out in order to increase the productivity of invertase expression using a recombinant Saccharomyces cerevisiae containing plasmid pRB58. Two batch cultures showed the expression of the SUC2 gene at a low concentration of glucose, suggesting that glucose concentration could be used as a control variable in a fed-batch operation mode. In the fed-batch culture by feeding the basal medium, cell mass and specific invertase activity did not increase much as compared with the simple batch culture. A series of fed-batch cultures revealed that the sucrose-supplemented medium increased cell mass whereas the enriched medium did specific invertase activity. To capitalize on the synergism of the sucrose-supplemented medium and the enriched medium, the sucrose-supplemented enriched medium was used as a feeding medium. The fed-batch culture using this medium resulted in a 2.4-fold increase in cell mass and a 1.9-fold enhancement in specific invertase activity compared with those of the batch culture. The increase in cell mass and specific invertase activity led to a marked increase in total invertase activity, 250U/ml, which was 6.3 times higher than that of the batch culture.

• The Korean Journal of Cytopathology
• /
• v.7 no.1
• /
• pp.59-63
• /
• 1996

Human sparganosis is a rare parasitic disease in which the larval cestode proliferates in the various organs in the body. It usually presents as a subcutaneous or soft tissue mass. By fine needle aspiration this lesion can be diagnosed with its characteristic cytologic findings. We experienced 3 cases of sparganosis diagnosed by the fine needle aspiration. Aspirates were taken from subcutaneous mass in the abdomen and both thighs respect ively. The aspirates showed a portion of body of sparganum with numerous calcospherules, smooth muscles and tegmental cells. They also revealed granulomas with various inflammatory infiltration of eosinophils, neutrophils, lymphocytes and plasma cells.