• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.2
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• pp.883-898
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• 2019

This paper employs computational tools to predict power increase (or speed loss) and propulsion performances in waves of KVLCC2. Two-phase unsteady Reynolds averaged Navier-Stokes equations have been solved using finite volume method; and a realizable k-ε model has been applied for the turbulent closure. The free-surface is obtained by solving a VOF equation. Sliding mesh method is applied to simulate the flow around an operating propeller. Towing and self-propulsion computations in calm water are carried out to obtain the towing force, propeller rotating speed, thrust and torque at the self-propulsion point. Towing computations in waves are performed to obtain the added resistance. The regular short head waves of λ/LPP = 0.6 with 4 wave steepness of H/λ = 0.007, 0.017, 0.023 and 0.033 are taken into account. Four methods to predict speed-power relationship in waves are discussed; Taylor expansion, direct powering, load variation, resistance and thrust identity methods. In the load variation method, the revised ITTC-78 method based on the 'thrust identity' is utilized to predict propulsive performances in full scale. The propulsion performances in waves including propeller rotating speed, thrust, torque, thrust deduction and wake fraction, propeller advance coefficient, hull, propeller open water, relative rotative and propulsive efficiencies, and delivered power are investigated.

• Journal of Internet Computing and Services
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• v.9 no.4
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• pp.1-10
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• 2008

In this paper, a packet scheduling algorithm, called the modified PLFS, is proposed for real-time traffic in IEEE 802.22 WRAN systems. The modified PLFS(Packet Loss Fair Scheduling) algorithm utilizes not only the delay of the Head of Line(HOL) packets in buffer of each user but also the amount of expected loss packets in the next-next frame when a service will not be given in the next frame. The performances of the modified PLFS are compared with those of PLFS and M-LWDF in terms of the average packet loss rate and throughput. The simulation results show that the proposed scheduling algorithm performs much better than the PLFS and M-LWDF algorithms.

• Korean Journal of Head & Neck Oncology
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• v.28 no.2
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• pp.114-117
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• 2012

Background and Objectives : To assure the surgical completeness of the gasless endoscopic thyroidectomy via single incision axillary approach using flexible videoscope which provide wide angle and working space, we compared single incision axillary approach and axillo-areolar approach by means of clinical, surgical outcomes. Materials and Methods : From March 2011 to July 2012, 24 patients who had underwent endoscopic thyroidectomy via transaxillary approach were enrolled. Of total, 17 patients underwent single incision axillary approach(group I) and the other 7 underwent axillo-areolar approach(group II). Results : Patient demographics, surgical indications were similar between the two groups. The operating time(group I 144.6min, group II 153.6 min ; p=.29), blood loss(group I : 55.4cc, group II : 35.7cc : p=.64), hospital stay(group I : 4.2days, group II : 4.4 days ; p=.65) were similar in the two groups. Overall, two patients in group I(2/17, 11.8%) experienced postoperative complications, including one hematoma and one seroma. Due to narrow working space, one patient was change to axillo-areolar approach during single incision axillary approach with $30^{\circ}$ rigid endoscope. Conclusion：Single incision axillary approach is safe and effective similar to other endoscopic thyroidectomy methods using flexible videoscope. Different with $30^{\circ}$ rigid endoscope, 10-mm flexible videoscope can put inside the axillary inicision site in different axis with endoscopic instruments. This difference in endoscopic axis help to prevent crash with endoscopic instrument.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.1
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• pp.25-33
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• 2021

This experiment was conducted to determine the effects of the pre- and post-harvest variable factors on the processed product of kimchi cabbage cultivated in semi-highland at summer time. Kimchi cabbage cultivar 'Chun Gwang' was grown in an open field and/or under a plastic greenhouse condition; it was stored at 0? after harvesting with low-density polyethylene (LDPE) film packaging. The pre-harvest characteristics growth parameters, fresh weight, head weight, no of leaves, leaf thickness, firmness, moisture content etc. were evaluated. The evaluated postharvest characteristics were fresh weight loss, appearance, trimming loss, SPAD value, moisture content and hue angle. The results show that the fresh weight and leaf thickness were higher in 'Chun Gwang' kimchi cabbages grown in the greenhouse than those in the field. However, the other evaluated factors were not affected by the type of cultural method. During the storage, the cabbage continued to decrease in fresh weight loss, trimming loss and moisture content. When compared to the kimchi cabbage showed significant difference in the fresh weight loss, trimming loss and moisture content during storage. It was confirmed that both cultural methods indoor- and outdoor did not show head growth parameters of 'Chun Gwang' kimchi cabbages on semi-high land at summer time. Although no difference in the growth before storage was observed, the evaluated characteristics like fresh weight loss etc. were influenced by cultural method as a pre-harvest factor. This study suggests that there were to be affected by pre-harvest factor during storage after harvest. In this study, an integrated management system combining relationship between processed agricultural products and their pre- and post-harvest factors.

• Food Science of Animal Resources
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• v.36 no.4
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• pp.445-451
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• 2016

The effect of reducing pork meat concentrations from 50% to 30% and replacing it with up to 20% pork head meat on chemical composition, cooking characteristics, physicochemical and textural properties, apparent viscosity, and sensory characteristics of frankfurters was determined. The highest moisture content in frankfurters was found in the control and T1 (frankfurter with 45% pork meat + 5% pork head). Protein and fat contents in frankfurters with pork head meat added were significantly (p<0.05) higher than those in the control. When the concentration of pork head meat was increased from 0% to 20%, cooking loss, total expressible fluid separation, fat separation, and pH of frankfurters were increased, while the lightness, redness, yellowness, and apparent viscosity of frankfurters were decreased. Ash contents, cohesiveness, color, and tenderness of sensory characteristics of frankfurters added with different amounts of pork meat or pork head meat were not significantly (p>0.05) different from those of the control or there treatments. Frankfurters in T4 (frankfurter with 30% pork meat + 20% pork head) had the lowest (p<0.05) hardness and gumminess. The hardness and gumminess of frankfurters in other treatments were not significantly different (p>0.05) from that in the control. Frankfurters with higher pork head meat concentrations had lower flavor, juiciness, and overall acceptability scores. Therefore, replacing pork meat with pork head meat in the formulation could successfully produce results similar to those of control frankfurters. The best results were obtained when 10% pork head meat was used to replace pork meat.

• Journal of Biosystems Engineering
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• v.40 no.1
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• pp.10-18
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• 2015

Purpose: The study was conducted to investigate the proper working conditions like the mesh size of the concave and the chaffer angle of the oscillating sieve, and the fan speed of the head-feeding rice combine for foxtail millet harvesting. Methods: The study aimed to determine the harvesting conditions for the rice combine harvester at a 0.5 m/s working speed and at $40^{\circ}$ and $55^{\circ}$ sieve chaffer angles. The harvesting loss of the foxtail millet based on the speed of the fan and the oscillating speed of the sieve was measured at three levels of fan speed and oscillating sieve speed. Results: The threshing rates of different foxtail millet varieties were 64.1~83.5% at a mesh size of 7 mm of the concave. In experimental foxtail millet harvesting, the optimal operating condition of the rice combine harvester included a $40^{\circ}$ sieve chaffer angle and a 4.8 Hz oscillating sieve (cleaning shoe) frequency. The grain loss was found to be lower at a $40^{\circ}$ than at a $55^{\circ}$ sieve chaffer angle. In field harvesting using the combine harvester, the lowest harvesting grain loss rate of the foxtail millet varieties ranged between 0.2~0.5% at a 7 mm mesh concave, $40^{\circ}$ chaffer angle, 4.8 Hz sieve frequency, and a 20 m/s fan speed at an engine speed of 2,000 revolutions per minute (RPM). Conclusions: Findings showed that foxtail millet could be harvested using the combine harvester.

• Fire Science and Engineering
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• v.27 no.3
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• pp.52-59
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• 2013

It was described the measured friction loss depending on pressure used and changes in water flow rates for a fire hose used at a fire scene on this study. As a result of actual measurement based on the result obtained by analyzing the use situation of a fire hose such as the kind, quantity, pressure used, etc. of a fire hose, the friction loss in a fire hose under the condition of using by a fire officer at a fire scene was measured as up to 56.8 %. This is much different from the equivalent length of a fire hose used to calculate the pump head in an indoor and outdoor fire-fighting facility. There is no related restrictive regulation on friction loss, there are even no data on friction loss measured by fire hose makers, and spreading a fire hose without considering friction loss at a fire scene can result in an increased length of hose used and a high-pressure water discharge from a fire engine, so this study aims to establish a standard for an equivalent length to friction loss in a fire hose and to propose a spreading method considering friction loss in a fire hose at a fire scene.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.3
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• pp.163-171
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• 2017

Effects of different packaging methods for maintaining the shelf life and postharvest quality of iceberg lettuce (Lactuca sativa L.) were studied after harvesting in summer season. Lettuce heads were packaged in plastic crate with or without different films such as (A) Individual lettuce head sealed packaging with linear low density polyethylene (LLDPE) film; (B) Packaging lettuce head in plastic crate and wrapped with LLDPE film; (C): Individual lettuce head sealed packaging with perforated high density polyethylene (HDPE) film; (D) Packaging lettuce head in plastic crate and wrapped with perforated HDPE; and (E) Packaging lettuce head in plastic crate without any film (control), and stored at $2^{\circ}C$ for 35 days. Several quality parameters such as fresh weight loss, SPAD (soil & plant analyzer development) meter value, respiration rate, moisture content and appearance of lettuce were investigated. The lettuce wrapped with individually-sealed LLDPE film showed the lowest weight loss and the highest SPAD value rendering the best appearance index among the treataments throughout the three-week storage period at $2^{\circ}C$. Extending the freshness of iceberg lettuce during low temperature storage will definitely increase the salability potential in the domestic market even during summer season.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.2
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• pp.168-173
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• 2006

The side effects of head and neck radiation therapy include mucositis, xerostomia, loss of taste, radiation caries, oral infection, osteoradionecrosis and trismus. When a patient is arranged to begin head & neck radiotherapy, oral pathologic lesions are examined and managed for the prevention of oral complications. The advanced odontogenic infection should be especially controlled before the radiotherapy and the patient must be instructed for proper oral prophylaxis. Generally the more conservative treatments, such as, scaling, restoration, endodontic treatment, are the care of choice and dental extraction is performed in advanced periapical and periodontal pathologic conditions. If the dental extraction should be done, the radiotherapy consequently will be delayed until there is epithelium covering the extraction socket, leaving no exposed bone. The cancer patient with severe emotional stress pray for the early radiation therapy, in spite of possibility of the recurrent odontogenic infectious lesions. So, the authors attempted to do the early radiation therapy by the conservative endodontic drainage and surgical incision & drainage without extraction of the infected teeth, and resulted in relatively good prognosis without the severe side effects of head and neck radiotherapy.

• Nuclear Engineering and Technology
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• v.30 no.2
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• pp.112-127
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• 1998

The present study is to assess the applicability of the best-estimate thermal-hydraulic codes, RELAP5/MOD3.2 and CATHARE2V1.3U, to the analysis of thermal-hydraulic behavior in PWRs during midloop operation following the loss of RHRS. The codes simulate an integral test, BETHSY 6.94, which was conducted in the large scale test facility of BETHSY in France. The test represents the accident where the loss of RHRS occurs during midloop operation with the pressurizer and upper head vents open and the sight level indicator broken. Besides, the hot legs are half filled with water and the upper parts of the primary cooling system are filled with nitrogen, with a letdown line open and only one SG available. The purposes of this study are to understand the physical phenomena associated with reflux cooling in the 5G U-tubes when noncondensable gas is present under low pressure and to assess the applicability of the codes to simulate the loss of RHRS event by comparing the predictions with the test results. The results of the study may contribute to actual applications for plant safety evaluation and description of the emergency operating procedure.