• Journal of the Korea Society for Simulation
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• v.23 no.4
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• pp.41-49
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• 2014

Detection and processing techniques for small objects on seabed by the active synthetic aperture sonar can be increased the detection performance because it can be used by short sensor array in small unmanned underwater systems that are spatially constrained. But the limited conditions on constant speed and straight movement of the platform cause a large error in the number of external environmental factors and exact phase synthesis process. In this study, analyzed the applicability of active synthetic aperture processing that is mounted on such a system, and compared detection resolution change in accordance with the phase difference mismatch caused by the along track disturbance. Various simulations were performed as a coherently focus processing model by adding along track disturbance mismatched parameter on the configuring simulator. As the result, detection performance of active synthetic processing for small objects on seabed was found a number of changes by the phase difference mismatch errors according to track disturbances and S/N ratio variations.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.6
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• pp.761-768
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• 1999

This paper is studied to find the optimum condition of double-inlet Sirocco fan installed in an indoor PAC for low noise operation by the Taguchi method. The goal of this study is to obtain the best combination of each control factor which results in a desired flowrate of Sirocco fan with minimum variability. In this study, the parameter design of the Taguchi method is adopted for robust design by the dynamic characteristic analysis using orthogonal arrays and S/N ratios. The flowrate measurements are conducted by using a multiple-nozzle-type fan tester according to the orthogonal array L9($3^4$). The results of this study can be summarized as follows ; (i) The optimum condition of control factor is a set of where A is an inner to outer diameter ratio($D_1/D_2$), B is a width to outer diameter ratio($L/D_2$), C is a blade attachment angle(${\theta}$) and D is a number of blade(Z), (ii) The flowrate under the optimum condition satisfies the equation $y=0.0384{\cdot}M$ where M is a signal factor, namely number of revolution. The flowrate performance improves about 7.3% more largely as compared with the current condition, which results in about 35RPM reduction of number of revolution for the target flowrate $18.5m^3/min$, and (iii) The sensitivity analysis shows that the major factors in contribution to flowrate performance are A, B, and D ; the percentage contributions of each control factor are 44.01%(Z), 26.77%($D_1/D_2$) and 20.42%($L/D_2$).

• Journal of the Korean Applied Science and Technology
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• v.30 no.2
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• pp.204-214
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• 2013

This research was performed to evaluate Vibrio fischeri toxicity for TNT-contaminated soils treated by composting and slurry phase bioreactor, which were operated for 45 and 200 days, respectively. In case of composting, the GL value of acetone-added soil was 40, which was lower than th at of glucose-added soil after treatment. In case of slurry phase bioreactors under anaerobic, anaerobic/aerobic, and aerobic regimes, they showed the GL values of 6, 8, and 4 after treatment, respectively. It was evaluated that the toxicity of all slurry phase bioreactors was reduced significantly to detoxification. The relationships between GL value and the number of S. typhimurium in both composting and slurry phase bioreactor were developed as the first order equations with high correlation coefficient (r > 0.8890).

• Journal of the Institute of Convergence Signal Processing
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• v.10 no.1
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• pp.32-39
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• 2009

In this paper, the method of region segmentation using genetic algorithm is proposed for an improvement of efficiency in moving picture coding. A genetic algorithm is the method that searches a large probing space using only a function value for a optimal combination consecutively. By progressing both motion presumption and region segmentation at once, we can assign the motion vector in a image to a small block or a pixel respectively, and transform the capacity of coding and a signal to noise rate into a problem of optimization. That is to say, there is close correlation between region segmentation and motion presumption in motion-compensated prediction coding. This is to optimize the capacity of coding and a S/N ratio. This is to arrange the motion vector in each block of picture according to the state of optimization. Therefore, we examined both the data type of genetic algorithm and the method of data processing to obtain the results of optimal region segmentation in this paper. And we confirmed the validity of a proposed method using the test pictures by means of computer simulation.

• The Korean Journal of Mycology
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• v.26 no.1 s.84
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• pp.39-46
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• 1998

This study was carried out to obtain the basic data for artificial culture of Sparassis crispa. The optimal conditions for the mycelial growth were $25^{\circ}C$ and pH 4, respectively. The mycelial density of S. crispa was most compact in the Hamada media, whereas colony diameter was prominent in the Hoppkins media. Carbon sources such as maltose, arabinose and mannitol were favorable for stimulating a mycelial growth of S. crispa. Glycine, one of nitrogen sources also appeared to be favorable to the mycelial growth. The optimum C/N ratio was about 20 : 1 in case that 1% glucose as carbon source was mixed with the basal medium. Fumaric acid or lactic acid as organic acid was most favorable to the mycelial growth.

• Journal of Mushroom
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• v.18 no.3
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• pp.268-273
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• 2020

This study aimed to assess the feasibility of composting spent mushroom substrate (SMS) materials of Lentinula edodes (Le), Hericium erinaceus (He), and Pleurotus ostreatus (Po). The different SMSs were composted for 7 to 10 days at high temperatures over 50℃; the composting procedure was completed in 30 days. A maturity test was conducted using the radish seed germination index and CoMMe-100. The composted SMS (CSMS) from Le and He showed gemination indices of 130% and 81%, respectively, that satisfied the criteria of maturity standard (gemination index over 70%) and the CoMMe-100 analysis. The physicochemical changes of CSMSs included an increase in the pH range from 4-5 to 6-7, slight reduction in the EC to 1-1.4 dS/m, and an organic content of 36.9% in LeCSMS. In LeCSMS, the contents of N, P, and K were 1.2%, 2.3%, and 0.77%, respectively, and heavy metals were detected below the standard value in all CSMSs; the Ca and Mg contents in the CSMSs were increased from 30% to 60% when compared to those in the SMSs. The C/N ratio (from 26-33) in LeSMS and HeSMS decreased to 15.3-15.9 in CSMSs. The growth effect of LeCSMS treatment on pepper seedlings was 60% higher than that in the control groups, one of which was treated with commercial organic compost; the former showed a superior growth effect on the leaf width, leaf length, and leaf number compared to other control groups. In conclusion, LeCSMS and HeCSMS could be utilized as compost resources capable of efficient soil amendment and plant growth promotion.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3135-3141
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• 2013

This study derives the optimal conditions for design parameters of clinch stud with high torque resistance and bonding force by using FE simulation and Taguchi method. Maximum forming load and filled rate of material are considered as objective functions. Height and depth of groove with diameter and depth of lobe are chosen as design parameters. These control factors and the friction considered as noise factor are combined by orthogonal array. Forming load and filled rate are evaluated through the simulation. Simulation results are analyzed by using the ratio of signal to noise through Taguchi method. From these results, their optimal combination conditions are proposed. In the order of the most important parameter which affects filled rate, there are the height of lobe, the height of groove, the radius of lobe and the depth of groove.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.12
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• pp.2004-2011
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• 2004

The applicability of the ultrasonic C-scan inspection is restricted due to the deterioration of mechanical properties of specimen during the test. Therefore, the aim of this research is applied to Eddy Current (EC) test substitute for the C-scan inspection in CFRP tube containing defects. This research is to evaluate the EC signals for the inspection of CFRP tube containing various circular hole defects (20% to 100% depth to the specimen thickness) using the unloading specimen and radial loading specimen. This study was considered the following points; 1) Analysis of EC signals for the inspection of saw-cut defect and circular hole defect, 2) The evaluation of defect depths and EC signals relationship. 3) Variation of EC signal owing to the radial load. In conclusions, the high frequency such as 300∼500 kHz made it possible to the inspection of 40% to 100% defects. Particularly, in case of 20% defect, the EC signal was not detected due to the noise of micro-crack and delamination. While the depth of the hole defects were decreasing, the difference of the phase angle between unloading specimen and radial loading specimen was gradually increasing.

• The Korean Journal of Mycology
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• v.30 no.1
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• pp.1-5
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• 2002

Cultural characteristics of Cordyceps militaris preserved in EFCC, Kangwon National University were investigated for the mass production. The higher mycelial density of C. militaris was observed in Sabouraud's yeast and Yeast Malt agars, but the higher mycelial growth in Mushroom Minimal agar than other agars. The mycelium of C. militaris was observed to grow well at $25^{\circ}C$ and pH 6.0 respectively. The dextrose was found the best suitable energy source among the carbohydrates used for its mycelial growth, while the fructose or lactose observed to be well for mycelial growth. Hemoglobin was observed to be the best among the protein sources used for mycelial growth, while tryptone found to be the best in the spore formation. Similarly, the mycelial growth was best in mineral salts of $KH_2PO_4$ or $K_2HPO_4$ and the optimum C/N ratio was 100 : 1.

• Journal of The Korea Institute of Healthcare Architecture
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• v.25 no.4
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• pp.27-35
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• 2019

Purpose: As the improvement in quality of medical environment and the spatial consideration for the prevention of infection in the hospital have become increasingly important in the recent years, specific and practical planning for air conditioning room's area has become a major issue accordingly. However, the air conditioning room tends to be discussed focusing on technical factors such as air conditioning systems that are irrelevant to building plans, while discussions of most departments related to the medical functions have actively taken placed. Therefore, this study aims to investigate the factors influencing the planning for the air conditioning room area, and through subsequent analysis of the area of the air conditioning room, to propose a way to improve effective planning for the air conditioning room area. Methods: This study examines the case hospitals that fall into two types: each floor supply system and concentrated supply system, and compares and analyzes the air conditioning room area-related factors and the characteristics of changes in the interior of air conditioning room before and after remodeling through air conditioning floor plan of those case hospitals. Results: The air conditioning room can be classified into the net area of the functional space such as duct passages, and the public area such as aisle space, and of those the public area is an important factor in calculating the area of the air conditioning room. The public area of the air-conditioning room should not be planned considering only the spaces for mobile passage or maintenance activities, but should be planned taking into account internal changes such as expansion and replacement of equipment in the future from the beginning. Implications: When planning a medical facility, it is used as basic data for the planning of the air conditioning room area, which is a significant fixed factor in the initial setting.