• Nuclear Engineering and Technology
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• v.18 no.3
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• pp.200-208
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• 1986

The loss of coolant accident based on a double-ended cold leg break is analyzed with the discharge coefficient (Ca) of 0.4. This analysis covers the whole transient period from the start of depressurization to the complete refilling of the core by using RELAP4/MOD6-EM and RELAP4/ MOD6-HOT CHANNEL for the system thermal-hydraulics and the fuel performance during the blowdown phase respectively, and RELAP4/MOD6-FLOOD and TOODEE2 during the reflood phase. A simple analytical method has been developed to account for the lower plenum filling by approximating steam-water countercurrent flows and superheated wall effects at the downcomer during the refill period. Based on the informations. at the time of EOB (end-of-bypass), the refill duration time and the initial reflooding temperature were estimated and compared with the results from the RELAP4/MOD6, resulting in a good agreement. In addition, some parametric studies on the EOB were performed. The form loss coefficient between upper head and upper downcomer was found to be sensitive to the occurrence of the spurious EOB. Appropriate form loss coefficients should be taken into account to avoid the flow oscillations at the downcomer. The analyses with the six and three volume core nodalizations, respectively, show much similar trends in the system thermal-hydraulic performance, but the former case is recommended to obtain good results.

• Journal of Korea Water Resources Association
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• v.47 no.7
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• pp.599-614
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• 2014

In this study, two dimensional finite volume model was parallelized to improve computing time, which has been developed to be able to apply for the mixed meshes of triangle and quadrilateral. MPI scheme which is free from limitation of the number of cores was applied, and non-blocking point-to-point communication was used for fluxes and time steps calculation domain. The developed model is applied to analyze dam break in a L-shaped experimental channel with $90^{\circ}$ bend and Malpasset dam breach event to calibrate the consistency between parallelized model and existing model and examine the speed-up and efficiency of computing time. Computational speed-up about the size of the input data was considered by simulating 4 cases classified by the number of meshes, Consequently, the simulation results reached a satisfactory accuracy compared to measured data and the results from existing model, and achieved more than 3 times benefit of computational speed-up against computing time of existing model. Simulation results of 3 cases classified by the size of input data lead us to the conclusion that it is important to use proper size of input data and the number of process in order to minimize the communication overhead.

• Journal of the Korean Geotechnical Society
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• v.30 no.2
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• pp.19-32
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• 2014

Carbonate sand of Sabkha layer in the middle east was made of deposition of shell fragments and it consisted of porous particles containing inner void. Generally, at yield stress the soil structure begins to break down, so the porewater pressure and the settlement are increased rapidly. In carbonate sand, unlike quartz sand if particle crushing happens, the inner voids are exposed and porewater pressure can be decreased under yield stress. Porewater pressure can be determined as the sum of excess porewater pressure due to increase of relative density, inner void expose of particle under particle crushing stress and rearrangement of crushed particle fragments. The porewater pressure can be negative value in case of greater amount of inner void expose, so if particle crushing is bigger, the porewater pressure value is smaller. The negative value zone of porewater pressure from triaxial test result means particle crushing effect is bigger than outer void decrease effect and the particle crushing effect dominant zone size was 1.50∼3.46% from triaxial test result of Sabkha layer.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.9
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• pp.1407-1413
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• 2015

The objective of this study was to investigate the rheological and pasting properties of potato flour dispersions at different concentrations (3, 4, 5, 6, and 7%, w/w). A potato cultivar 'Goun', used in this study, was developed by Highland Agriculture Research Center, RDA. Potato flour dispersions showed shear-thinning behaviors (n=0.44~0.51) at $25^{\circ}C$. Apparent viscosity (${\eta}_{a,100}$), consistency index (K), and yield stress (${\sigma}_{oc}$) significantly increased with an increase in potato flour concentration. Storage modulus (G') and loss modulus (G") significantly increased, whereas complex viscosity (${\eta}^*$) was significantly reduced with increasing frequency (${\omega}$) from 0.63 to 63.8 rad/s. Magnitudes of G' and G" were significantly increased with elevation of potato flour concentration. G' values were considerably greater than G" over the entire range of frequency (${\omega}$) with a high dependence on ${\omega}$. Cox-Merz rule was not applicable to potato flour dispersions. Rapid Visco Analyzer data showed that peak viscosity, trough viscosity, breakdown viscosity, final viscosity, and set back viscosity of samples significantly increased with an increase in potato flour concentration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.2
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• pp.268-274
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• 2015

Makgeolli residue protein (MRP) was extracted from byproduct of makgeolli processing, and MRP films containing various plasticizers were prepared. Among the plasticizers used in this study, MRP film containing glycerol-sorbitol (1:2) showed the most desirable mechanical properties. In addition, MRP films containing wasabi extract (WE) were prepared by incorporating different amounts (0, 0.8, 1.0, and 1.2%) of WE into film-forming solution. Tensile strength, elongation at break, and moisture content of MRP films decreased with addition of WE as compared with the control. However, MRP films containing WE showed antimicrobial activities against Escherichia coli O157:H7 and Listeria monocytogenes. Application of MRP film containing 1.0% WE to beef packaging decreased populations of E. coli O157:H7 and L. monocytogenes after storage at $4^{\circ}C$ for 8 days by 1.1 and 0.41 log CFU/g, respectively, compared with those of the control. In addition, the peroxide value and 2-thiobarbituric acid reactive substance value decreased by 53 and 56%, respectively, compared to the control. Therefore, these results suggest that MRP film containing WE can be used to improve the quality of beef during storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.3
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• pp.410-414
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• 2013

Styela (S.) clava (Korean name: miduduk) tunic is produced as a by-product after processing of S. clava. For utilizing this tunic, a konjac containing the tunic extracts was prepared and the qualities evaluated for their color, textural properties, and sensory attributes. The tunic extract was prepared by boiling tunic with water, followed by filtration through filter paper. Significant 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging activity was found in the tunic extract. Increasing the concentration of tunic extract in the konjac tended to decrease lightness (L) and increase the redness (a) and the yellowness (b) of the konjac. The strength and hardness of the konjac increased with increasing concentrations of the tunic extract. All test samples with a 3 mm thickness had good flexibility and did not break even after 4 times folds. In sensory evaluations, the konjac containing 25% S. clava tunic extracts acquired a relatively higher score. The results suggest that S. clava tunic can be applied to konjac products to improve their quality and functionality.

• Science of Emotion and Sensibility
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• v.19 no.3
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• pp.51-58
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• 2016

This study examined the difference between the deaf and hearing adolescents of experiencing emotions and the intensity levels of expressing them. Three different video clips were used to induce pleasure, anger, and sadness. While watching the clips, facial expressions of the participants were recorded. The experienced emotions were measured by a self-report method, and the third person rated participants' expressed emotions based upon the recorded facial images. Two groups (deaf and hearing) were compared if those two groups shared the same experienced emotions, and whether the ratings scored by the third person corresponded with the self-rated scores. There was no significant difference in experienced emotion and its intensity level. However, hearing adolescents showed more intensive responses of pleasure than they reported, while deaf adolescents showed less intensive expressions of happiness than they reported themselves. Thus, hearing people might not be able to detect and fully comprehend how the deaf feel in general circumstances. This further indicates that the deaf adolescents cannot get enough supports from the hearing people when they express their feelings, and consequently, have a possibility of causing misunderstandings, conflicts, or even a break in relationships.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1883-1886
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• 2005

In this paper, a decoupled dual servo (DDS) stage for ultra-precision scanning system with large working range is introduced. In general, dual servo systems consist of a fine stage for short range and a coarse stage for long range. The proposed DDS also consists of a $XY\theta$ fine stage for handling and carrying workpieces and one axis coarse stage. Its coarse stage consists of air bearing guide system and a coreless linear motor with force ripple. The fine has four voice coil motors(VCM) as its actuator. According to a VCM's nature, there are no mechanical connections between coils and magnetic circuits. Moreover, VCM doesn't have force ripples due to imperfections of commutation components of linear motor systems - currents and flux densities. However, due to the VCM's mechanical constraints the working range of the fine is about $25mm^2$. To break that hurdle, the coarse stage with linear motors is used to move the fine about 500mm. Because of the above reasons, the proposed DDS can achieve higher precision scanning than other stages with only one servo. With MATLAB's Sequential Quadratic Programming (SQP), the VCMs are optimally designed for the highest force under conditions and constraints such as thermal dissipations due to its coil, its size, and so on. And for their movements without any frictions, guide systems of the DDS are composed of air bearings. To get precisely their positions, a linear scale with 5nm resolution are used for the coarse stage's motion and three plane mirror laser interferometers with 5nm for the fine's $XY\theta$ motions. With them, on scanning the two stages have same trajectories. The control algorithm is named Parallel method. The embodied ultra-precision scanning system has sub 100nm following error and in-positioning stability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.10
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• pp.1703-1708
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• 2004

This study was carried out to investigate the characteristic quality of jeungpyun added Paecilomyces japonica with different fermentation time. The volume of jeungpyun added Paecilomyces japonica was more increased after fermentation. The volume was decreased when the fermentation was progressed. The pH was 5.1 before fermentation and the pH decreased when the fermentation was progressed. Moisture content was more increased as the time of fermentation became longer. Hunter color test, L value and b value appeared the highest after 1st fermentation, and it appeared lesser when the time of fermentation became longer. In measurement of texture, hardness showed the highest value when 90 minutes passed after the 2nd fermentation. Gumminess and brittleness were tend to increase when it have longer fermentation time. In scanning electron microscopic observation, organization of sponges was tend to break down as the fermentation time was longer. Sensory properties showed that color intensity was more strong when second fermentation was progressed, and hardness, toughness, sourness were high when the fermentation time was longer. In conclusion overall acceptability of jeungpyun, 3$0^{\circ}C$, 3 hours after 1st fermentation and 2nd fermentation for 30 minutes, 35$^{\circ}C$ showed the most preference.

• Journal of Advanced Navigation Technology
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• v.20 no.4
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• pp.374-379
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• 2016

Recently, IoT(Internet of Things) to connect the objects and people has attracted attention. And it is rapidly developing. IoT is to develop, experts are predicting that the device is connected to the Internet to break through around 100 billion within 10 years. However, the current IoT companies are having a difficult state to the other each other IoT platform for interaction between data silos effects. These silos effects will limit the IoT grow to a larger market. Thus, the IoT service supplier shall develop an open platform for interaction IoT data between each IoT platform. These web technologies for current open IoT platform has emerged. If developers are using familiar, easy-to-learn Web technologies, developers can take advantage of a variety of services for the collected data, and found the IoT devices can be bypassed if there is a problem on the network. In this paper, we investigate the data communications technology that can be used in WoT environment to overcome these silos effects. As a result, the polling method that can simply send the IoT information the fastest.