• Atmosphere
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• v.29 no.5
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• pp.671-687
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• 2019

This study evaluates the long-term seasonal predictability of summer (June, July and August) heatwaves over South Korea using 30-year (1989~2018) Hindcast data of the Pusan National University Coupled General Circulation Model (PNU CGCM)-Weather Research and Forecasting (WRF) chain. Heatwave indices such as Number of Heatwave days (HWD), Heatwave Intensity (HWI) and Heatwave Warning (HWW) are used to explore the long-term seasonal predictability of heatwaves. The prediction skills for HWD, HWI, and HWW are evaluated in terms of the Temporal Correlation Coefficient (TCC), Root Mean Square Error (RMSE) and Skill Scores such as Heidke Skill Score (HSS) and Hit Rate (HR). The spatial distributions of daily maximum temperature simulated by WRF are similar overall to those simulated by NCEP-R2 and PNU CGCM. The WRF tends to underestimate the daily maximum temperature than observation because the lateral boundary condition of WRF is PNU CGCM. According to TCC, RMSE and Skill Score, the predictability of daily maximum temperature is higher in the predictions that start from the February and April initial condition. However, the PNU CGCM-WRF chain tends to overestimate HWD, HWI and HWW compared to observations. The TCCs for heatwave indices range from 0.02 to 0.31. The RMSE, HR and HSS values are in the range of 7.73 to 8.73, 0.01 to 0.09 and 0.34 to 0.39, respectively. In general, the prediction skill of the PNU CGCM-WRF chain for heatwave indices is highest in the predictions that start from the February and April initial condition and is lower in the predictions that start from January and March. According to TCC, RMSE and Skill Score, the predictability is more influenced by lead time than by the effects of topography and/or terrain feature because both HSS and HR varies in different leads over the whole region of South Korea.

• Journal of the Ergonomics Society of Korea
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• v.30 no.5
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• pp.637-644
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• 2011

Objective & Background: When applying various evaluation tools that analyze work posture risk through observation, accurate measurement of body flexion angle is very important. Method: This study investigated differences and appropriateness of 5 different existing reference points commonly used in the analysis of the work posture. Twenty five ergonomist and trained professionals were participated in this study. A Same flexion angle was utilized for the evaluation of risk assessment of musculoskeletal disorders using five different reference points to investigate the degree of difference between them. To investigate how different the observers' preferred flexion angle measuring methods were compared to the ISO 11226 Reference Posture, a virtual body model was constructed using the Poser 6.0 program. Six types of body flexion postures were constructed, and since neck flexion differs according to body angle, five types of neck flexion postures were constructed with the trunk bending $20^{\circ}$ forward, making up a total of 30 virtual flexion postures. Results: Results showed that the observers used personally preferred reference points instead of reference points recommend in the evaluation tools. Also the results revealed the their seems to be 6 types of flexion angle for the trunk and 11 types of measurement methods for the neck flexion angle in the form of personally preferred reference points. The results showed that a mean difference of $14^{\circ}$($4{\sim}23^{\circ}$) occurred in the trunk, and a mean difference of $20^{\circ}$($-8{\sim}51^{\circ}$) occurred in the neck. To increase accuracy when using the 5 evaluation tools in combination, the ISO 11226 standards, observers' preferred flexion posture standards, and common flexion posture standards of the evaluation tools were compared with the reference points of the 5 evaluation tools. Results showed considerable variance in angle difference for each evaluation tool. Conclusion: According to the results of this study, considering the angle difference between the flexion angle reference points of the evaluation tool and the reference points selected by the observers, it is concluded that instead of personally preferred reference points, the standardized reference points to enhance the accuracy and the objectivity. Application: The result of this study can be used as reference guide to develop the standardized reference point in the future.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.2
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• pp.225-230
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• 1999

In mouse, the heat shock protein 70-2 (hsp70-2) is found to have special function in spermatogenesis. Based on the observation, the hypothesis that human hspA2 (human gene; 98.2% amino acid homology with hsp70-2) might have important function in spermatogenesis in human testes was proposed. To test the hypothesis, we examined the expression of hspA2 in human tissues. Expression vector pDMC4 for expression of the human hspA2 protein using pTricHisB (invitrogen, USA) was constructed and the expressed hspA2 protein was cross-reacted with antiserum 2A raised against mouse hsp70-2 protein. Based on the cross-reactivity, we determined the expression level of hspA2 protein in human tissues by western blot analysis using the antiserum 2A. We demonstrated that antiserum 2A antibodies detected human hspA2 protein with specificity which was produced in the E.coli expression system. On Western blot analyses, significant hspA2 expression was observed in testes with normal spermatogenesis, whereas a low level of hspA2 was expressed in testis with Sertoli-cell only syndrome. Also, a small amount of hspA2 was detected in breast, stomach, prostate, colon, liver, ovary, and epididymis. These results demonstrate that the hspA2 protein is highly expressed in male specific germ cells, which in turn suggests that hspA2 protein might playa specific role during meiosis in human testes as suggested in the murine model. However, further studies should be attempted to determine the function of hspA2 protein in human spermatogenesis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1959-1963
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• 2014

The feasibility of incorporating flaxseed powder up to 8% (w/w) as a value-added food ingredient in convenient food products was investigated using pound cake as a model system. The moisture content, volume, height, and hardness of cakes decreased significantly with increasing levels of flaxseed powder (P<0.05). On the other hand, baking loss increased with higher flaxseed powder in the formulation (P<0.05). Lightness and yellowness decreased, whereas redness increased significantly (P<0.05). 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) radical scavenging activities increased significantly (P<0.05), and they were well correlated. The consumer acceptance test indicated that addition of 2% flaxseed powder had the most favorable effect on consumer preferences in general. Based on the overall observation, pound cakes with 2% flaxseed powder is recommended to take advantage of its functional properties without sacrificing consumer acceptability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1174-1180
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• 2014

This study investigated the antioxidative and hair growth-promoting activities of Zizyphus jujuba (Zj) and fermented Zj with Aspergillus oryzae, Bacillus subtilis, Bifidobacterium breve, Lactobacillus acidophilus, and Saccharomyces cerevisiae (Sac. cerevisiae). Among Zj and fermented Zjs, Sac. cerevisiae-fermented Zj (Zj-Y) exerted stronger scavenging activity against 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radicals than others. In addition, total polyphenol content of Zj-Y was higher than that of non-fermented Zj and other fermented Zj. This result indicates that fermentation of Zj by Sac. cerevisiae elevated antioxidative activity. Furthermore, using an alopecia model in C57B/6N mice, the hair growth activities of Zj and Zj-Y were investigated. The test samples, EtOH, minoxidil (MXD), Zj, and Zj-Y, were topically treated with 0.2 mL/day for 4 weeks. The experiments involved macroscopic observation and measurement of hair length methods. The results show that regrowth speed of hair was in decreasing order of MXD> Zj-Y> Zj> EtOH. The topical application of MXD and Zj-Y in mice promoted hair regrowth and prevented hair loss compared to the control group. The present study indicates that Zj-Y is a promising treatment for alopecia.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.1
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• pp.84-97
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• 2010

Landscape urbanism emerges as an alternative to the urban design theories of the past century, emphasizing landscape as an organizing principle, integrating the medium of different elements of the urban environment. However, ongoing criticism of the theory's lack of consideration for physical urban morphology has not supported the integrity of the theory. Large parks, which many proponents of the theory have referred to, possess valuable and interesting points in their design and management. This also shows the limitation of not being able to show the close physical relationship between open space and the city. In this study, the High Line project was analyzed to verify it as founded on landscape urbanism, providing that landscape urbanism drives the urban morphology on a small scale rather than a large one. This paper concludes that landscape urbanism should include small parks as one kind of study model with the small grained interaction between open spaces and the cities under this category to broaden and deepen the perspective. Also, the effort to analyze quantified and physical consequences of the theory through close observation should be followed to extract the design strategies to be applied to future projects.

• Journal of Positioning, Navigation, and Timing
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• v.6 no.3
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• pp.125-133
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• 2017

Time comparison is necessary for the verification and synchronization of the clock. Two-way satellite time and frequency (TWSTFT) is a method for time comparison over long distances. This method includes errors such as atmospheric effects, satellite motion, and environmental conditions. Ionospheric delay is one of the significant time comparison error in case of the carrier-phase TWSTFT (TWCP). Global Ionosphere Map (GIM) from Center for Orbit Determination in Europe (CODE) is used to compare with Bernese. Thin shell model of the ionosphere is used for the calculation of the Ionosphere Pierce Point (IPP) between stations and a GEO satellite. Korea Research Institute of Standards and Science (KRISS) and Koganei (KGNI) stations are used, and the analysis is conducted at 29 January 2017. Vertical Total Electron Content (VTEC) which is generated by Bernese at the latitude and longitude of the receiver by processing a Receiver Independent Exchange (RINEX) observation file that is generated from the receiver has demonstrated adequacy by showing similar variation trends with the CODE GIM. Bernese also has showed the capability to produce high resolution IONosphere map EXchange (IONEX) data compared to the CODE GIM. At each station IPP, VTEC difference in two stations showed absolute maximum 3.3 and 2.3 Total Electron Content Unit (TECU) in Bernese and GIM, respectively. The ionospheric delay of the TWCP has showed maximum 5.69 and 2.54 ps from Bernese and CODE GIM, respectively. Bernese could correct up to 6.29 ps in ionospheric delay rather than using CODE GIM. The peak-to-peak value of the ionospheric delay for TWCP in Bernese is about 10 ps, and this has to be eliminated to get high precision TWCP results. The $10^{-16}$ level uncertainty of atomic clock corresponds to 10 ps for 1 day averaging time, so time synchronization performance needs less than 10 ps. Current time synchronization of a satellite and ground station is about 2 ns level, but the smaller required performance, like less than 1 ns, the better. In this perspective, since the ionospheric delay could exceed over 100 ps in a long baseline different from this short baseline case, the elimination of the ionospheric delay is thought to be important for more high precision time synchronization of a satellite and ground station. This paper showed detailed method how to eliminate ionospheric delay for TWCP, and a specific case is applied by using this technique. Anyone could apply this method to establish high precision TWCP capability, and it is possible to use other software such as GIPSYOASIS and GPSTk. This TWCP could be applied in the high precision atomic clocks and used in the ground stations of the future domestic satellite navigation system.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.36 no.3
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• pp.111-115
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• 2014

Purpose: This study evaluated powdered burn wound dressing materials from wild silkworm fibroin in an animal model. Methods: Fifteen rats were used in this experiment. Full-thickness $2{\times}2cm$ burn wounds were created on the back of rats under anesthesia. In the two experimental groups, the wounds were treated with two different dressing materials made from silkworm fibroin. In the Control Group, natural healing without any dressing material was set as control. The wound surface area was measured at five days, seven days and 14 days. Wound healing was evaluated by histologic analysis. Results: By gross observation, there were no infections or severe inflammations through 14 days post-injury. The differences among groups were statistically significant at seven days and 14 days, postoperatively (P<0.037 and 0.001, respectively). By post hoc test, the defect size was significantly smaller in experimental Group 1 compared with the Control Group and experimental Group 2 at seven days postoperatively (P=0.022 and 0.029, respectively). The difference between Group 1 and Group 2 was statistically significant at 14 days postoperatively (P<0.001). Group 1 and control also differed significantly (P=0.002). Group 1 showed a smaller residual scar than the Control Group and Group 2 at 14 days post-injury. Histologic analysis showed more re-epithelization in Groups 1 and 2 than in the Control Groups. Conclusion: Burn wound healing was accelerated with silk fibroin spun by wild silkworm Antheraea pernyi. There was no atypical inflammation with silk dressing materials. In conclusion, silk dressing materials can be used for treatment of burn wound.

• Journal of Digital Convergence
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• v.17 no.12
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• pp.435-444
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• 2019

The purpose of this study was to investigate the relationship between sleep duration and muscle strength in Korean adults aged 19 years and older. The cross-sectional analysis was conducted using the 2016 National Health and Nutrition Examination Survey data and Chi square test and multiple regression analysis were used. As a result of the analysis, the grip strength of those with more than weekday average sleep duration of 9 hours was found to be -1.267kg compared with those with weekday average sleep duration of 7 hours. The grip strength of those with more than weekend average sleep duration of 9 hours was found to be -0.879kg compared with those with weekend average sleep duration of 7 hours. In model simultaneously adjusting for both the average weekday and weekend average sleep duration, weekday average sleep duration of 9 hours was found to be -1.034kg compared with those with weekday average sleep duration of 7 hours. Therefore, careful observation will be required in light of the fact that both sleep duration and grip strength can predict future health conditions.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.7
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• pp.209-220
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• 2014

In this paper, we analyze the discriminability of features for the classification of transient signals with an ambient noise in a shallow water. For the classification of the transient signals, robust features for the variance of a noise are required due to a low SNR under a marine environment. In the modelling the ambient noise in shallow water, theoretical noise model, Wenz's observation data from the shallow water, and Yule-walker filter are used. Discrimination of each feature of the transient signals with an additive ambient noise is analyzed by utilizing a Fisher score. As the analysis of a classification accuracy about the transient signals of 24 classes using the selected features with a high discriminability, the features selected in the environment without a noise relatively have a good classification accuracy. From the analyzed results, we finally select a total 16 features out of 28 features. The recognition using the selected features results in the classification accuracy of 92% in SNR 20dB using Multi-class SVM.