• Korean Journal of Poultry Science
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• v.46 no.4
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• pp.223-234
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• 2019

This study investigated the effects of thawing methods and storage time on the quality of frozen duck meat. Meat was obtained from eight-week-old Korean native ducks (average weight=2.8 kg). Seventy-two samples were divided into eight treatments (three replicates/treatment, three samples/replicate) with 2 × 4 factorial arrangement based on two thawing methods (under running water at 12℃ for 3 h and in a refrigerator at 5℃ for 24 h) and four storage times (1, 3, 6, and 12 months). CIE b^* was significantly different among different storage time treatments, reaching its lowest after 6 months (P<0.05). Cooking loss did not differ between storage times; however, it was significantly lower following application of the fast thawing treatment (P<0.05). Water-holding capacity of meat stored for one month was highest compared to that of meat stored for a longer period (P<0.05). Additionally, there were significant differences based on storage time in γ-linoleic acid (C18:3n6) and eicosenoic acid (C20:1n9) contents (P<0.01), as well as in protein contents (P<0.05). Palmitoleic acid (C16:1n7) typically decreased after three months of storage; however, this decline was not significant compared to other storage times. Essential amino acids contents, except methionine, were significantly difference at six and 12 months of storage (P<0.05). Similarly, non-essential amino acid contents, except tyrosine, were significantly different among storage periods (P<0.05, P<0.01). Alternatively, there were no significant differences in the chemical composition, fatty acid content, or amino acid content based on the thawing method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.345-353
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• 2020

On conventional railway lines, trains with different speeds are operated. Therefore, trains moving on curved sections with cants must accept various ranges of balanced cants, cant deficiency, and cant excess, which is essential for the comfort and safety of train operation. In this study, the correlation between the curve radius, cant, and train speed on a track was analyzed to check the cant range that satisfies the criteria of train types, operation speed, cant deficiency, and cant excess. Also, the range of setting the cant by the curve radius and balanced cant were calculated by a regression analysis of train speed according to the frequency of operation in the case of mixed trains. The results could make it possible to improve the speed of the operation route, reduce the loss of ride quality, reduce the risk of derailing caused by cant deficiency, and minimize the load deflection by excess cant. This will ensure the safety of trains running on curves and improve the efficiency of track maintenance.

• Journal of Environmental Impact Assessment
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• v.24 no.5
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• pp.432-443
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• 2015

Ski industry is sensitive to climate change. Many studies were carried out to learn the impact on climate change to large scale ski resorts around the world and the results are difficult to be applied to small scale ski resorts in general. So, this study targeted small ski resorts composing the ski industry of Korea and forecasted the impact of climate change. As a result, based on the mitigation efforts to minimize climate changes of the future (RCP 4.5), ski industry could be maintained at the same level of today. However, if climate change continues at the current trend (RCP 8.5), ski resorts will face loss of business days. If 100 days are considered as the minimum days to maintain the ski business, among 17 ski resorts in Korea, 3 ski resorts will be driven out of business by 2030s, 12 more ski resorts by 2060s and remaining 2 ski resort by 2090s will end the business. It means that smaller ski resorts has higher chance of facing difficulties in running business just as large scale ski resorts. Therefore, to sustain the ski business, technical and managerial efforts to adapt to the changing environment is needed.

• The KIPS Transactions:PartD
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• v.14D no.2
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• pp.249-264
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• 2007

As the need for telematics contents services due to the frequent traveling of people is increasing, it is necessary to provide various telematics contents by connecting and integrating current telematics contents which are collected and provided by each individual data provider. However, it is difficult to integrate or exchange the current telematics contents, because the data providers use different telematics contents models. Therefore, we propose a 'telematics contents gateway(TCG); system, which enables to integrate different telematics contents, so that the contents can be interoperable. The TCG can be a solution for several problems in the current telematics contents providing system. First of all, it has been impossible to search the contents without any information about data providers, because of the absence of metadata in the current systems. For this problem, TCG supports a search function based on a web-service technology. Second, TCG provides a common road network model for interoperability, and the model can be a solution to integrate different road network models into the common model. Moreover, integration algorithm for enhancing the correctness of integration will be proposed. In addition, it is designed by multi threads and multi queue structure. The TCG developed with C# on a windows system has been running and we verified that there was no information loss in the integration process. In addition, the speed of content integration and transfer satisfied the requirement of telematics services providers.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11A
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• pp.882-890
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• 2009

In this paper, we describe a compensation method that can be used for the situation where Loran receivers lose their phase lock to the received Loran signals when Loran signals are employed for the synchronization of national infrastructures such as telecommunication networks, electric power distribution and so on. In losing the phase lock to the received signals in a Loran receiver, the inner oscillator of the receiver starts free-running and the performance of the timing synchronization signals which are locked to the oscillator's phase is very severly degraded, so the timing accuracy under 1 us for a Primary Reference Clock (PRC) required in the International Telecommunications Union (ITU) G.811 standard can not be satisfied in the situation. Therefore, in this paper, we propose a method which can compensate the phase jump by using a compensation algorithm when a Loran receiver loses its phase lock and the performance evaluation of the proposed algorithm is achieved by the Maximum Time Interval Error (MTIE) of the measured data. From the performance evaluation results, it is observed that the requirement under 1 us for a PRC can be easily achieved by using the proposed algorithm showing about 0.6 us with under 30 minutes mean interval of smoothing with 1 hour period when the loss of phase lock occurs.

• Korean Journal of Environment and Ecology
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• v.35 no.3
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• pp.294-304
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• 2021

This study aims to obtain basic data for systematic restoration by analyzing the monitoring results of the Shimwon Valley Ecological Landscape Restoration Project area in Jirisan National Park. In 2017, when the restoration project was completed, 12 monitoring plots and 4 control plots were installed for vegetation monitoring, and changes in the relative dominance, species diversity index and similarity between 2017 and 2020 were analyzed. The species diversity index of the surveyed areas where trees were planted during the restoration project was 0-1.4552, and the similarity index with the control group was 0% except for one survey area at 1.32%. The very low species diversity index and similarity index in the survey areas were attributed to the loss of trees planted during the restoration project due to death, damage by wild boars, or erosion by running water. On the other hand, the species diversity index was 0.9538-2.3222 in the monitoring plot where no tree was planted, and the similarity index was analyzed to be as high as 8.33%. It is necessary to continue the long-term monitoring for the development of ecological landscape restoration methods in the national park and analysis of the succession in monitoring plots where no trees were planted.

• Journal of Life Science
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• v.33 no.3
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• pp.277-286
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• 2023

Sarcopenia is the age-related loss of muscle mass and function. It is a natural part of aging and can lead to decreased mobility and increased frailty. The ubiquitin-proteasome pathway, which is involved in muscle protein degradation, is closely linked to sarcopenia. Germinated Rhynchosia nulubilis hydrolysate (GRH) has been reported to have anti-inflammatory and antioxidant properties, but there have been no reports on its inhibitory effect on muscle reduction. However, no study has yet explored the relationship between GRH and muscle loss inhibition. In this study, we evaluated the effects of GRH on muscle atrophy inhibitory activity in dexamethasone (Dexa)-induced muscle atrophy C2C12 myotubes and mouse models. Moreover, we identified a molecular pathway underlying the effects of GRH on skeletal muscle. May Grunwald-Giemsa staining showed that the length and area of myotubes increased in the groups treated with GRH. In addition, the GRH-treated group significantly reduced the expression of muscle ring finger protein 1 and muscular atrophy F-box (MAFbx) in the Dexa-induced muscular atrophy C2C12 model. GRH also improved muscle strength in C57BL/6 mice with Dexa-induced muscle atrophy, resulting in prolonged running exhaustive time and increased grip strength. We found that muscle strengthening by GRH was correlated with a decreased expression of the MAFbx gene in mouse muscle tissue. In conclusion, GRH can attenuate Dexa-induced muscle atrophy by inhibiting the ubiquitin-proteasome pathway via downregulation of the MAFbx gene expression.