• 한국체육학회지인문사회과학편
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• v.58 no.4
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• pp.447-459
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• 2019

This study was conducted to investigate the differences between emotional responses and neurotransmitters in moderate-intensity continuous exercise (MICE) and high-intensity interval exercise (HIIE) in 30 low-active women. Both groups performed a designed acute treadmill exercise and repeated the same exercise three times at intervals of one week. MICE performed a 25-minute continuous exercise at 90% VT(ventilation threshold) after a 5-minute warm-up session at 50% VT and then cooled down for 5 minutes at 50% VT level. The HIIE was repeated 6 times for 2 minutes at 115% VT level, and the intermediate active recovery was repeated 4 times for 2 minutes at 85% VT level. The results of the statistical analysis are as follows. MICE was showed positive effect for feeling scale and PACES after exercise in the first experiment, but negative effect in the third experiment. Conversely, HIIE was showed negative effect for feeling scale and PACES after exercise in the first experiment, but positive effect in the third experiment. Neurotransmitters were significantly increased in all three groups after 10 minutes of exercise compared to before exercise. In summary, HIIE exercise may be a strategy to increase exercise compliance for low-active women.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2014.10a
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• pp.25-48
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• 2014

Increased frequency of climate extremes is another face of climate change confronted by humans, resulting in catastrophic losses in agriculture. While climate extremes take place on many scales, impacts are experienced locally and mitigation tools are a function of local conditions. To address this, agrometeorological early warning systems must be place and location based, incorporating the climate, crop and land attributes at the appropriate scale. Existing services often lack site-specific information on adverse weather and countermeasures relevant to farming activities. Warnings on chronic long term effects of adverse weather or combined effects of two or more weather elements are seldom provided, either. This lecture discusses a field-specific early warning system implemented on a catchment scale agrometeorological service, by which volunteer farmers are provided with face-to-face disaster warnings along with relevant countermeasures. The products are based on core techniques such as scaling down of weather information to a field level and the crop specific risk assessment. Likelihood of a disaster is evaluated by the relative position of current risk on the standardized normal distribution from climatological normal year prepared for 840 catchments in South Korea. A validation study has begun with a 4-year plan for implementing an operational service in Seomjin River Basin, which accommodates over 60,000 farms and orchards. Diverse experiences obtained through this study will certainly be useful in planning and developing the nation-wide disaster early warning system for agricultural sector.

• KEPCO Journal on Electric Power and Energy
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• v.8 no.2
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• pp.159-179
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• 2022

Often a network becomes complex, and multiple entities would get in charge of managing part of the whole network. An example is a utility grid. While the entire grid would go under a single utility company's responsibility, the network is often split into multiple subsections. Subsequently, each subsection would be given as the responsibility area to the corresponding sub-organization in the utility company. The issue of how to make subsystems of adequate size and minimum number of interconnections between subsystems becomes more critical, especially in real-time simulations. Because the computation capability limit of a single computation unit, regardless of whether it is a high-speed conventional CPU core or an FPGA computational engine, it comes with a maximum limit that can be completed within a given amount of execution time. The issue becomes worsened in real time simulation, in which the computation needs to be in precise synchronization with the real-world clock. When the subject of the computation allows for a longer execution time, i.e., a larger time step size, a larger portion of the network can be put on a computation unit. This translates into a larger margin of the difference between the worst and the best. In other words, even though the worst (or the largest) computational burden is orders of magnitude larger than the best (or the smallest) computational burden, all the necessary computation can still be completed within the given amount of time. However, the requirement of real-time makes the margin much smaller. In other words, the difference between the worst and the best should be as small as possible in order to ensure the even distribution of the computational load. Besides, data exchange/communication is essential in parallel computation, affecting the overall performance. However, the exchange of data takes time. Therefore, the corresponding consideration needs to be with the computational load distribution among multiple calculation units. If it turns out in a satisfactory way, such distribution will raise the possibility of completing the necessary computation in a given amount of time, which might come down in the level of microsecond order. This paper presents an effective way to split a given electrical network, according to multiple criteria, for the purpose of distributing the entire computational load into a set of even (or close to even) sized computational loads. Based on the proposed system splitting method, heavy computation burdens of large-scale electrical networks can be distributed to multiple calculation units, such as an RTDS real time simulator, achieving either more efficient usage of the calculation units, a reduction of the necessary size of the simulation time step, or both.

• Journal of the Korean Geotechnical Society
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• v.37 no.11
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• pp.61-69
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• 2021

In this study, scale down model bridge piers were fabricated and non-destructive experiments conducted with an impact load to determine scours in the ground adjacent to the bridge piers using the natural frequency of the bridge piers. Three scale-model bridge piers with different heights were fabricated, and they penetrated the ground at a depth of 0.35 m. The scours around the bridge piers were simulated as a side scour and foundation scour. The experiments were conducted in 13 steps, in which scouring around the model bridge piers was performed in 0.05 m excavation units. To derive the natural frequency, the impact load was measured with three accelerometers attached to the model bridge piers. The impact load was applied with an impact hammer, and the top of the model bridge pier was struck perpendicularly to the bridge axis. The natural frequency according to the scour progress was calculated with a fast Fourier transform. The results demonstrated that the natural frequency of each bridge pier tended to decrease with scour progress. The natural frequency also decreased with increasing pier height. With scour progress, a side scour occurred at 70% or higher of the initial natural frequency, and a foundation scour occurred at less than 70%.

• Journal of the Korean GEO-environmental Society
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• v.22 no.12
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• pp.65-70
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• 2021

River-side Embankment collapse involves various causes. The embankment collapse due to internal erosion around embedded structures reaches up to more than 10% in Korea. Many studies are being attempted to prevent from the collapse of the embankment rooted from overtopping and instability as well as internal erosion. One of them is the study on the application of biopolymers. The application of biopolymers to soils are divided into enhancing strength, vegetation and erosion resistance. This study investigated the effect of biopolymer treated soil on erosion resistance. The main goal of the study is to obtain basic data for real-scale experiments to verify the effectiveness of biopolymer treated soil embankment including a review of the collapse pattern in the model embankment with various test conditions. The optimized experimental conditions were selected by examining the erosion patterns according to each induction path with three compaction degree of the model embankment. As a result of the experiment, the internal erosion rate in the embankment to which the biopolymer treated soil was applied is greatly reduced, and it could be concluded that it might be applied to the actual embankment. However, in this study, the conclusion was drawn only within the scaled-down model embankment. In order to practically apply the biopolymer treated soil to the embankment, the study considering the scale effect would be needed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.243-249
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• 1996

To formalize the mechanization technique so as to build up competitiveness on the international market, a detail survey of a 104ha size rice farm, was made. And calculated to find out how many machine of each calibre are needed. It was found that he needed : 3 farm tractors, 3 combines, 4 grain dryers, 1 speed sprayer, 100 man days of labor for sowing, application of fertilizer and herbicide, respectively. And also needed 150 man days for combine harvesting and 60 man days for disease and pest control. It was found also that well timed harvesting is critically needed to keep rice quality. Because, in case when harvesting machine was beakdown to make harvesting time extended, then the quality drops down very much and also the farm income fall very much. Therefore, it is recommended that the amount of machine needed should be prepared and they should be well maintained so that harvest be completed in time.

• Korean Journal of Radiology
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• v.23 no.8
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• pp.811-820
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• 2022

Objective: To develop a model incorporating radiomic features and clinical factors to accurately predict acute ischemic stroke (AIS) outcomes. Materials and Methods: Data from 522 AIS patients (382 male [73.2%]; mean age ± standard deviation, 58.9 ± 11.5 years) were randomly divided into the training (n = 311) and validation cohorts (n = 211). According to the modified Rankin Scale (mRS) at 6 months after hospital discharge, prognosis was dichotomized into good (mRS ≤ 2) and poor (mRS > 2); 1310 radiomics features were extracted from diffusion-weighted imaging and apparent diffusion coefficient maps. The minimum redundancy maximum relevance algorithm and the least absolute shrinkage and selection operator logistic regression method were implemented to select the features and establish a radiomics model. Univariable and multivariable logistic regression analyses were performed to identify the clinical factors and construct a clinical model. Ultimately, a multivariable logistic regression analysis incorporating independent clinical factors and radiomics score was implemented to establish the final combined prediction model using a backward step-down selection procedure, and a clinical-radiomics nomogram was developed. The models were evaluated using calibration, receiver operating characteristic (ROC), and decision curve analyses. Results: Age, sex, stroke history, diabetes, baseline mRS, baseline National Institutes of Health Stroke Scale score, and radiomics score were independent predictors of AIS outcomes. The area under the ROC curve of the clinical-radiomics model was 0.868 (95% confidence interval, 0.825-0.910) in the training cohort and 0.890 (0.844-0.936) in the validation cohort, which was significantly larger than that of the clinical or radiomics models. The clinical radiomics nomogram was well calibrated (p > 0.05). The decision curve analysis indicated its clinical usefulness. Conclusion: The clinical-radiomics model outperformed individual clinical or radiomics models and achieved satisfactory performance in predicting AIS outcomes.

• Journal of Microbiology
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• v.39 no.1
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• pp.67-73
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• 2001

A validation study was conducted to evaluate the efficacy and mechanism of the cryo-precipitation, monoclonal anti-FVIIIc antibody (mAb) chromatography, Q-Sepharose chromatography, and lyophilization steps involved in the manufacture of high purity factor VIII (GreenMono) from human plasma, in the removal and/or inactivation of hepatitis A virus (HAV). Samples from the relevant stages of the production process were spiked with HAV and subjected to scale-down processes mimicking the manufacture of the high purity factor VIII concentrate. Samples were collected at each step and immediately titrated using a 50% tissue culture infectious dose (TCID$\_$50/) and then the virus reduction factors were evaluated. HAV was effectively partitioned from factor VⅢ during cryo-precipitation with the log reduction factor of 3.2. The mAb chromatography was the most effective step far removal of HAV with the log reduction factor of $\geq$4.3. HAV infectivity was not detected in the fraction of factor VⅢ, while most of HAV infectivity was recovered in the fractions of flow through and wash during mAb chromatography. Q-Sepharose chromatography showed the lowest efficacy for partitioning HAV with the log reduction factor of 0.7. Lyophilization was an effective step in inactivating HAV with the log reduction factor of 2.3. The cumulative lag reduction factor, $\geq$10.5, achieved for tile entire manufacturing process was several magnitudes greater than the potential HAV load of current plasma pools.

• Corrosion Science and Technology
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• v.14 no.2
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• pp.47-53
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• 2015

Recently, the bending process is greatly applied to fabricate the pipe line. Bending process can reduce welding joints and then decrease the number of inspection. Thus, the maintenance cost will be reduced. Induction heat bending process is composed of bending deformation by repeated local heat and cooling. By this thermal process, corrosion properties and microstructure can be affected. This work focused on the effect of induction heating bending process on the properties of ASME SA106 Gr. C low carbon steel pipes. Microstructure analysis, hardness measurements, and immersion corrosion test were performed for base metal and bended area including extrados, intrados, crown up, and down parts. Microstructure was analyzed using an optical microscope and SEM. Hardness was measured using a Rockwell B scale. Induction heat bending process has influenced upon the size and distribution of ferrite and pearlite phases which were transformed into finer structure than those of base metal. Even though the fine microstructure, every bent area showed a little lower hardness than that of base metal. It is considered that softening by the bending process may be arisen. Except of I2, intrados area, the others showed a similar corrosion rate to that of base metal. But even relatively high rate of intrados area was very low and acceptable. Therefore, it is judged that induction heat bending process didn't affect boric acid corrosion behaviour of carbon steel.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2002.04a
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• pp.17-24
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• 2002

Mechanization is the characteristic of the industrial era and computerization is the characteristic of the Information Era. Now we are facing on the transition from Industrial Era to information Era. Established the National Geo-spatial Data Infrastructures is the fundamental base for information society and is one part of the national basic economic development plan. From 1980's China started his successful transition from traditional methods to high-tech based mapping. China has laid out a high accuracy national GPS (global Positioning System) network, and completed the geographic information databases for scale of 1:1million and 1:250,000. Now it is working on the databases for scales of 1:50,000 and 1:10,000, the world highest level. The massive national programmed has been dubbed "Digital China," since it involves massive quantities of digitized geographical information. Simultaneity, GIS technology and the geo-spatial data have been used widely in electronic government affair, environmental protection, disaster control, ITS and etc. The users have realized the benefits more and more widely. Internet is an efficient way to distribute the geo-information, the State Bureau of Surveying and Mapping has give great effort to settle down the rules and standards to establish the clearing house. Some National Geo-standards have issued, and some of them are on the way. The GIS software is another important factor in the GIS industry. Chinese government working-out some good policy to supports the GIS software developer to have their own copyright. This paper is based on the above to introduce the status and development of Geomatics in China. in China.