• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.4
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• pp.876-893
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• 2014

The resistance performance of an icebreaking cargo vessel according to the variation of waterline angles is investigated numerically and experimentally. A recently developed Finite Element (FE) model is used in our analysis. A resistance test with synthetic ice is performed in the towing tank at Pusan National University (PNU) to compare and validate the computed results. We demonstrate good agreement between the experimental and numerical results. Shipice interaction loads are numerically calculated based on the Fluid Structure Interaction (FSI) method in the commercial FE package LS-DYNA. Test results from model testing with synthetic ice at the PNU towing tank are used to compare and validate the numerical simulations. For each waterline angle, numerical and experimental comparisons were made for three concentrations (90%, 80%, and 60%) of pack ice. Ice was modeled as a rigid body, but the ice density was the same as that used in the experiments. A comparative study according to the variation of stem angles is expected to be conducted in the near future.

• Journal of the Korea Convergence Society
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• v.11 no.10
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• pp.25-30
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• 2020

In this study, a test system which can test performance of curling pad was developed to support Korea curling team. The developed system consists of a water tank, a mechanical pad driving system that can perform sweeping movement using a curling pad on surface of ice made by the water tank, and temperature sensors monitoring ice and air temperatures. To control the temperature of ice and humidity/temperature of air around the ice, all system are installed in a chamber that can isolate the developed system from external environment. Eight kinds of curling pads were tested using the developed system. Test result showed that each curling pad revealed different rate of ice temperature increasing. The pad with the highest rate of ice temperature rising was found to be the same as the most preferred pad by the athletes. Therefore, it was confirmed that the method of measuring change of ice temperature by the sweeping performed in this study is an effective method to test the performance of the pad.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.11
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• pp.1088-1094
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• 2005

In the present paper, a new method is proposed for the measurement of the ice packing factor (IPF) of an ice slurry using the index of refraction. The purpose of the new method is to improve the resolution of the measurement and to increase its resistance to electric noise as compared to the standard IPF measurement technique that relies on measurement of the freezing temperature. These two methods are similar in that they both obtain a concentration of aqueous solution from measured physical quantities and calculate the IPF using a relation between concentration and IPF. We experimented and compared the two methods, whose results were also compared with results from the calorimeter method obtaining the IPF directly They are in good agreement (within $5\%$), which demonstrates the validity of the newly proposed method.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.326-336
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• 1997

Four ice nucleation-active bacteria (INA-bacteria), Pseudomonas syringae, Xanthomonas campestris, Escherichia coli JM109/pEIN229 and Gluconobacter oxydans/pKIN230, were treated with heat, pressure and gamma-irradiation to compare viability and their ice nucleation activity (INA) after sterilization. Gamma-irradiated INA-bacteria showed the least decrease in T90 value (the temperature at which the 90% of drops are frozen). According to cumulative INA spectra, gamma-irradiated INA-bacteria showed little decrease in class A ice nuclei $(nucleate\;H_{2}O\;at\;higher\;than\;-5^{\circ}C)$, pressurized INA-bacteria showed more than 90% decrease in class A ice nuclei, and heat-treated INA-bacteria barely showed class A ice nuclei. Differential scanning calorimetry (DSC) was used to examine the effect of INA-bacteria on the thermophysical properties of water at freezing temperature. Freezing peaks were appeared at about $11{\sim}15^{\circ}C$ higher on thermograms and enthalpies of phase change were decreased for the water containing INA-bacteria compared with the pure water, while melting peaks were not shifted. INA measured by DSC method were significantly correlated with INA measured by drop freezing method $(R^{2}>0.993,\;p<0.0001)$, indicating that DSC can be used as a new, simple and precise method for measuring INA.

• Journal of the Korean Applied Science and Technology
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• v.37 no.4
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• pp.860-869
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• 2020

This study was conducted to see the effect of maintaining the freshness of mackerel caught offshore, through the chemical analysis method in seawater slurry ice(SS), sea water cube ice(SC), tap water slurry ice(TS) and tap water cube ice(TC). Among each ice mass, bacteria were below the drinking water standard and ammonia nitrogen was over the threshold of 11 mg/l in sea water. The turbidity of the seawater was severe compared to that of fresh water. Proximate compositions showed 72.7% moisture content, 20.5% protein, 5.25% lipid, and 1.3% ash content. Sea slurry ice was kept low in pH compared with fresh water ice. VBN increases were inhibited in all reservoirs at the beginning of the storage. Generally Sea ice was kept lower VBN value than the fresh water ice.

• Journal of Ocean Engineering and Technology
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• v.28 no.2
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• pp.126-132
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• 2014

In this study, a method for analyzing the collision and interaction between ice bergy bits and a Mark III type liquid natural gas (LNG) carrier was considered, and the structural safety of a ship's hull and cargo containment system (CCS) was evaluated. In the analysis, a constitutive model implementing the strain rate dependant mechanical property was used to consider the typical material characteristics of ice rationally. A relatively simple and easy ice structure interaction analysis procedure, compared with the accurate but complicated FSI analysis scheme, was suggested. When the ice bergy bits collided with ship's side hull under the four assumed scenarios, the structural behaviors of the ship structure and LNG CCS were simulated by applying the suggested ice collision analysis procedure using the commercial hydro-code LS-DYNA. In addition, the effects of the shapes and colliding speed of the ice bergy bits on the ice-structure interaction and safety of the CCS were examined in detail.

• Korean Journal of Applied Biomechanics
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• v.17 no.4
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• pp.169-179
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• 2007

The purpose of this study was to investigate the relations between the segments of the body and to qualitatively analyze coordination pattern of joints and segments during Sweep Shot movement in Ice Hockey, by utilizing coordination variables was angle vs. angle plots. By the utilization the three dimensional anatomical angle cinematography, the angles of individual joint and segment according to sweep shot in ice hockey. The subjects of this study were five professional ice hockey players. The reflective makers were attached on anatomical boundary line of body. For the movement analysis three dimensional cinematographical method(APAS) was used and for the calculation of the kinematic variables a self developed program was used with the LabVIEW 6.1 graphical programming(Johnson, 1999) program. By using Eular's equations the three dimensional anatomical Cardan angles of the joint and ice hockey stick were defined. The three dimensional anatomical angular displacement and coordination pattern of trunk and Upper limb(shoulder-elbow, elbow-wrist linked system) showed important role of sweep shot in ice hockey. As the result of this paper, for the successful movement of sweep shot in ice hockey, it is most important role of coordination pattern of trunk-shoulder, shoulder-elbow and elbow-wrist. specially turnk movememt as a proximal segment. Coordination pattern of Upper Limb(upperarm-forearm-hand) of Sweep Shot movement in Ice Hockey that utilizes coordination variables seems to be one of useful research direction to understand basic control mechanisms of Ice hockey sweep shooting linked system skill. this study result showed flexion-extension, adduction-abduction and internal-external rotation of trunk are important role of power and shooting direction coordination pattern of upper Limb of Sweep Shot movement in Ice Hockey.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.460-463
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• 2010

Ice accretion on aircraft surface can greatly impair the aerodynamic performance of aircraft. As an alternative to the traditional Lagrangian particle tracking approach, an Eulerian-based droplet impingement and ice accretion code for air flows containing water droplets was developed A CFD solver was also developed to solve the clean airflow. The results of present method were compared with experimental data and previous icing codes such as LEWICE and FENSAP-ICE and were confirmed to show good agreement each other in qualitative and quantitative ways.

• Preventive Nutrition and Food Science
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• v.18 no.4
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• pp.269-272
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• 2013

This study was performed to compare the performance of Sanita-Kun dry medium culture plate with those of traditional culture medium and Petrifilm dry medium culture plate for the enumeration of the mesophilic aerobic bacteria in milk, ice cream, ham, and codfish fillet. Mesophilic aerobic bacteria were comparatively evaluated in milk, ice cream, ham, and codfish fillet using Sanita-Kun aerobic count (SAC), Petrifilm aerobic count (PAC), and traditional plate count agar (PCA) media. According to the results, all methods showed high correlations of 0.989~1.000 and no significant differences were observed for enumerating the mesophilic aerobic bacteria in the tested food products. SAC method was easier to perform and count colonies efficiently as compared to the PCA and PAC methods. Therefore, we concluded that the SAC method offers an acceptable alternative to the PCA and PAC methods for counting the mesophilic aerobic bacteria in milk, ice cream, ham, and codfish fillet products.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.10a
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• pp.416-421
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• 2021

In case of the road slips due to heavy snow and the temperature drops below 0 degrees, black ice which mainly occurs on the road, bridges for vehicles, and tunnel entrances, is not recognized by the driver's view because the image of the asphalt is transmitted through it. So cars' slip situation occurs, which leads to a big traffic accident and a large amount of loss of life and property. This study proposes a method to check the road condition using an infrared camera and to identify black ice through deep learning.