• Journal of Soil and Groundwater Environment
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• v.17 no.5
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• pp.49-55
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• 2012

A 1.28 L-batch reactor and continuous-flow stirred tank reactor (CFSTR) fed with formate and trichloroethene (TCE) were operated for 120 days and 56 days, respectively, to study the effect of formate as electron donor on anaerobic reductive dechlorination (ARD) of TCE to cis-1,2-dichloroethylene (c-DCE), vinyl chloride (VC), and ethylene (ETH). In batch reactor, injected 60 ${\mu}mol$ TCE was completely degraded in the presence of 20% hydrogen gas ($H_2$) in less than 8 days by anaerobic dechlorination mixed-culture (300 mg-soluble protein), Evanite Culture with ability to completely degrade tetrachloroethene (PCE) and -TCE to ETH under anaerobic conditions. Once the formate was used as electron donor instead of hydrogen gas in batch or chemostat system, the TCE-dechlorination rate decreased and acetate production rate increased. It indicates that the concentration of hydrogen produced in both systems is possibly more close to threshold for homoacetogenesis process. Soluble protein concentration of Evanite culture during the batch test increased from 300 mg to 688 mg for 120 days. Through the protein monitoring, we confirmed an increase of microbial population during the reactor operation. In CFSTR test, TCE was fed continuously at 9.9 ppm (75.38 ${\mu}mol/L$) and the influent formate feed concentration increased stepwise from 1.3 mmol/L to 14.3 mmol/L. Injected TCE was accumulated at 18 days of HRT, but TCE was completely degraded at 36 days of HRT without accumulation of the injected-TCE during the left of experiment period, getting $H_2$ from fermentative hydrogen production of injected formate. Although c-DCE was also accumulated for 23 days after beginning of CFSTR operation, it reached steady-state in the presence of excessive formate. We also evaluated microbial dynamic of the culture at different chemical state in the reactor by DGGE (denaturing gradient gel electrophoresis).

• Food Science of Animal Resources
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• v.32 no.4
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• pp.396-403
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• 2012

This study was conducted in order to investigate the effect of storage temperature abuse on the freshness of refrigerated and frozen spent hen's meat. After a room temperature storage condition, two different storage temperature were followed: refrigeration and frozen storage. All parts of the spent hen's meats were thawed at 4 d intervals up to 3 times (2, 6, and 10 d) for 24 h. The level of bacteria on the different parts of the refrigerated and frozen meats was higher than 6 Log CFU/g under the following storage conditions: refrigerated - breast, 12 h; leg, 6 h; wing, 12 h at the $1^{st}$ analysis, frozen - breast, 12 h at the $2^{nd}$ analysis; leg, 24 h at the $1^{st}$ analysis; wing, 12 h at the $1^{st}$ analysis. The pH value for the leg meat was higher than breast and wing meats. In the color measurements, under the room temperature storage condition, lightness and redness values decreased but the yellowness increased in refrigerated meats (p<0.05). The K-value regarding refrigerated leg meats exceeded 60%, which is the threshold value to evaluate the degree of freshness, during the $1^{st}$ analysis (p<0.05). The VBN value of refrigerated leg meat was the highest and reached up to 96.93 mg%. Thus, studies regarding the possible decline in quality according to the change of storage temperature could be used in order to establish a basic database for the quality control of spent hen meat being traded with other countries.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.13-13
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• 2011

The Rio Grande Compact Commission, in collaboration with local water management entities, water users and universities established a three state Rio Grande The Rio Grande Compact Commission, in collaboration with local water management entities, water users and universities established a three state Rio Grande Salinity Management Program. The objectives of the Rio Grande Project Salinity Management Program are to reduce salinity concentrations, loading, and salinity impacts in the Rio Grande basin for the 270 mile river reach from San Acacia, New Mexico to Fort Quitman, Texasto increase usable water supplies for agricultural, urban, and environmental purposes. The focus of this first phase of the program is the development of baseline salinity and hydrologic information and a preliminary assessment of the economic impacts of salinity. An assessment of the economic impacts of salinity in this region was conducted by scientists at Texas A&M University's AgriLife Research Center at El Paso and New Mexico State University. Economic damages attributable to high salinity of Rio Grandewater were estimated for residential, agricultural, municipal, and industrial uses. The major impact issues addressed were: who is being affected the types of economic impacts the magnitude of economic damages overall and by user category and identification of threshold-effect levels for different types of water use. Salinity concentrations in this 270 mile reach of the river typically range from 480 ppm to 1,200 ppm, but can exceed 3,000 ppm in the lower section of this reach. Economic impacts include reductions in agricultural yields, reduced water appliance life, equipment replacement costs, and increased water supply costs. This preliminary economic assessment indicates annual damages of $10.5 million from increased water salinity. Under current water uses, municipal and industrial uses account for 75% of the total estimated impacts. However, agricultural impacts are based on current crop pattern yield reductions and, salinity leaching requirements and do not account for the impacts of reduced revenue from having to grow salinity tolerant, lower value crops. Actual damages are anticipated to be significantly higher with the inclusion of these additional agricultural impacts plus the future impacts from the growing population in the region. A more comprehensive economic analysis is planned for the second phase of this program. Results of the economic analysis are being used to determine the feasiblity of salinity control alternatives and what salinity reduction control measures will be pursued.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.76-91
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• 2019

There have been many studies to examine the patterns in innovations reflecting industry-specific characteristics from an evolutionary economics perspective. The purpose of this study is to identify industry-specific differences in product innovation patterns and determinants of innovation performance. For this, Korean manufacturing is classified into high-tech industries and low-tech industries according to technology intensity. It is also pointed out that existing research does not reflect the decision-making process of firms' R&D implementations. In order to solve this problem, this study presents a Heckman sample selection model and a double-hurdle model as alternatives, and analyzes data from 1,637 firms in the 2014 Survey on Technology of SMEs. As a result, it was confirmed that the determinants and patterns of manufacturing in small and medium-size enterprise (SME) product innovation are significantly different between high-tech and low-tech industries. Also, through an extended empirical model, we found that there exist a sample selection bias and a hurdle-like threshold in the decision-making process. In this study, the industry-specific features and patterns of product innovation are examined from a multi-sided perspective, and it is meaningful that the decision-making process for manufacturing SMEs' R&D performance can be better understood.

• International Area Studies Review
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• v.22 no.4
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• pp.3-18
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• 2018

In this study, I examined capital market shock reaction effects of 29 OECD countries with the past 24 years sample period consisting of daily stock market return using T-GARCH model focused on volatility feedback hypothesis. US daily stock market return is used as a unique independent variable in this model in consideration of its characteristics of biggest market share and as an origin country of Global Financial Crisis. As a result, France, Finland, and Mexico in order are shown to be the strongest countries in the aspect of return spillovers from US. Canada, Mexico, and France are shown to be the highest countries in the aspect of explanatory power of model. The degrees of shock reaction are proved to be higher in order in Germany, Chile, Switzerland, and Denmark and those of downside shock reaction are seen higher in order in Greece, Great Britain, Australia, and Japan. Canada and Mexico belonging to NAFTA are shown to be higher in the return spillover from US and in the model explanatory power, but they are shown to be lower in the impact of shock reaction, suggesting that regional distance effect or gravity theory cannot be applied to financial spillovers any longer. In the analysis of subsample period of Global Financial Crisis, north American three countries do not show any consistent results as in the full sample period but shock reaction in the European countries are shown to record stronger, suggesting that shocks from US in the Crisis Times are transferred mainly to European region.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.267-274
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• 2019

To investigate the effect of high-intensity interval training (HIIT) on the outcomes of cardiac rehabilitation(CR) in elderly and younger patients with myocardial infarction(MI). Of the MI patients who received hospital-based CR from 2015 to 2017, we retrospectively reviewed the medical records of the patients who continued follow-up through the outpatient clinic. A total of 39 patients (20 elderly patients (${\geq}60year$($64.1{\pm}3.6$)) and 19 younger patients (< 60 year($55.6{\pm}2.3$)) was included in this study. The HIIT program was composed of 10 minutes of warm-up, 30 minutes of interval aerobic exercise, and 10 minutes of cool down. The aerobic exercise based on their initial exercise tolerance test outcome consisted of 3-minute usual intensity phase (60-70% of heart rate/VO2 reserve) and 4-minute of high-intensity phase (70-90% of heart rate/VO2 reserve). Exercise capacity was measured by exercise tests before and after hospital- based CR. Before CR, elderly group had a significantly lower exercise capacity in Exercise time, peak VO2, METs, Anaerobic threshold, VEmax, 02pulse than younger group. Both group showed similar improvement of cardiopulmonary exercise capacity after CR. And HIIT is safe and effective in elderly patients. It is considered necessary to further expansion for the participation of high intensity interval training in elderly patients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.295-302
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• 2018

Face recognition (FR) has been widely used in various applications, such as smart surveillance systems, immigration control in airports, user authentication in smart devices, and so on. FR in well-controlled conditions has been extensively studied and is relatively mature. However, in unconstrained conditions, FR performance could degrade due to undesired characteristics of the input face image (such as irregular facial pose variations). To overcome this problem, this paper proposes a new method for determining if an input image is suitable for FR. In the proposed method, for an input face image, reconstruction error is computed by using a predefined set of reference face images. Then, suitability can be determined by comparing the reconstruction error with a threshold value. In order to reduce the effect of illumination changes on the determination of suitability, a preprocessing algorithm is applied to the input and reference face images before the reconstruction. Experimental results show that the proposed method is able to accurately discriminate non-frontal and/or incorrectly aligned face images from correctly aligned frontal face images. In addition, only 3 ms is required to process a face image of $64{\times}64$ pixels, which further demonstrates the efficiency of the proposed method.

• New Physics: Sae Mulli
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• v.68 no.11
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• pp.1192-1195
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• 2018

We studied the electrical properties of organic thin-film transistors (OTFTs) fabricated at different deposition rates by measuring the field-effect mobility and the threshold voltages. As the active layer, pentacene thin film with a thickness of 50 nm was deposited at a rate of $0.05{\AA}/s$ to $1.14{\AA}/s$. The thickness of the drain-source gold electrode was 50 nm. The mobility was $1.9{\times}10^{-1}cm^2/V{\cdot}s$ at a deposition rate of $0.05{\AA}/s$, the mobility increased to $5.2{\times}10^{-1}cm^2/V{\cdot}s$ when the deposition rate was increased to $0.4{\AA}/s$, and then the mobility decreased to $6.5{\times}10^{-1}cm^2/V{\cdot}s$ when the deposition rate decreased to $1.14{\AA}/s$. Thus, the mobility of pentacene OTFTs was observed to depend on the thermal deposition rate.

• Journal of Industrial Convergence
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• v.19 no.6
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• pp.21-35
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• 2021

The purpose of this paper is to examine how demand for labor affects the job seeker's decision on the level of investment in education. In the current paradigm of economic growth in which innovations and technological developments generally weaken the strength demand for labor and increases the uncertainty related to employment, this paper provides a theoretical framework that can be used as a basic framework in understanding the decision of investment in education in varying conditions of demand for labor. The following are the findings of this paper. First, the level of investment in education can generally be regarded to be higher as the demand for labor exacerbates but for the job seekers with a certain characteristic. Second, the Arrow-Pratt absolute risk-aversion measure is the characteristic of the job seeker that determines in what direction the job seeker changes in the level of investment in education, For an arbitrary level of demand for labor there exists a certain threshold which determines the minimum degree of risk-aversion required for the job seeker's Arrow-Pratt should go over to increase the level of education as demand for labor weakens. Third, the job seekers lower the level of education even though the demand condition in labor markets weakens if the compensation function does not depend on the level of education. This is surprising because it turns out that one of the reasons why job seekers invest in education is that they want to be recognized in their compensation for their level of education even when more education still raises the probability of employment.

• Korean journal of applied entomology
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• v.61 no.2
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• pp.349-356
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• 2022

Fall armyworm, Spodoptera frugiperda, is a invasive migratory pest of native to the tropical and sub-tropical regions that has recently invaded Korea with damage to cornfield. The study was conducted to investigate the development periods of S. frugiperda on artificial diet at six different temperatures. The developmental period from eggs to adult at 18, 21, 24, 27, 30 and 32℃ was 79.8, 54.2, 34.3, 28.4, 24.6 and 24.0 days, respectivery and decreased with increasing temperature. The pupal periods of females were shorter than males. Most of the larvae developed through six instar, but the ratio of 7 or more instar increased at low temperatures. The relationship between the development rate and temperature was fitted with by linear regression analysis. The lower development threshold for egg and larva development was 12.9℃ and 11.3℃, respectively, 12.6℃ for pupae and 11.8℃ for egg-to-adult development. The effective accumulative temperature for the development of the respective life cycle stages were 37.0 DD for eggs, 286.3 DD for larvae, 132.2 DD for pupae and 456.8 DD egg-to-adult development.