• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.2
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• pp.65-73
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• 2016

We estimated the averaged maximum incidences of bacterial canker at suitable sites for kiwifruit cultivation in 2020s and 2050s using D-PSA-K model with RCP4.5 and RCP8.5 climate change scenarios. Though there was a little difference between the estimation using RCP4.5 and that using RCP8.5, the estimated maximum disease incidences were more than 75% at all the suitable sites in Korea except for some southern coastal areas and Jeju island under the assumption that there are a plenty of infections to cause the symptoms. We also analyzed the intermediate and final outputs of D-PSA-K model to find out the trends on the change in disease incidence affected by climate change. Whereas increase of damage to kiwifruit canes in a non-frozen environment caused by bacterial canker was estimated at almost all the suitable sites in both the climate change scenarios, rate of necrosis increase caused by the bacterial canker pathogen in a frozen environment during the last overwintering season was predicted to be reduced at almost all the suitable sites in both the climate change scenarios. Directions of change in estimated maximum incidence varied with sites and scenarios. Whereas the maximum disease incidence at 3.14% of suitable sites for kiwifruit cultivation in 2020s under RCP4.5 scenario was estimated to increase by 10% or more in 2050s, the maximum disease incidence at 25.41% of the suitable sites under RCP8.5 scenario was estimated so.

• Environmental and Resource Economics Review
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• v.16 no.2
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• pp.275-311
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• 2007

Hydrogen energy is emphasized as a substitutable energy of carbon-based energy system in the future, since it is non-depletable and clean energy. Long term vision of Korean government on the national energy system is to promote hydrogen energy by 15% of final energy demand until 2040. This study analyzes economic impacts of hydrogen energy development employing a dynamic CGE model for Korea. Frontier technology such as hydrogen energy is featured as slow diffusion at the initial stage due to the learning effect and energy complementarity. Without government intervention, hydrogen energy would be produced upto 6.5% of final energy demand until 2040. However, if government subsidizes sales price of hydrogen energy by 10%, 20%, and 30%, share of hydrogen energy would increase 9.2%, 15.2%, and 37.7% of final energy demand. This result shows that the slow diffusion problem of hydrogen energy as frontier technology could be figured out by market incentive policy. On the other hand, production levels of transportation sector would increase while growth rate of oil and electricity sectors would decline. Household consumption would be affected negatively since increase of consumption due to the price decrease would be overwhelmed by income reduction owing to the increase of tax. Overall, GDP would not decrease or increase significantly since total production, investment, and export would increase even if household consumption declines.

• Applied Biological Chemistry
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• v.38 no.2
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• pp.151-156
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• 1995

Single-drop splash/detachment studies and multiple-drop splash/detachment experiments were carried out to measure detachment by single and multiple drops. A raindrop tower 7.0 m in height was used to study soil splash by single drop raindrop impact over time on repacked soil samples in containers 76.2 mm in diameter. The waterdrop diameter and kinetic energy were 4.1 mm and $1.22{\times}10^{-3}$ J $drop^{-1}$, respectively. The samples consisted of five agricultural topsoils sieved to <2 mm, varying from sandy loam to clay loam in texture. The average weight of splashed soil particles after 75 drops did not show any significant difference between the five soils. The average weight of particles splashed by the first 15 drops showed that the sandy Pelham soil splashed to a greater degree than the others, and was therefore more detachable (p=0.05) than the other soils. The average weight of particles splashed by the last 15 drops also showed that the Pelham soil was the most detachable, with Cecil, Appling, Dyke, and Worsham soils being progressively less detachable. The effect of multiple drops on detachment was studied under a nozzle-type rainfall simulator at 74.9 mm $h^{-1}$ intensity for 85 min using the same soils as the single drop experiments. The total soil splash value for 85 min on Appling, Cecil, Dyke, Pelham, and Worsham soils were 6121, 6206, 4183, 5160, and 3247 g $m^{-2}$, respectively. There were no obvious relationships between soil loss measured from the different experiments.

• Journal of KIISE:Software and Applications
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• v.34 no.3
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• pp.226-234
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• 2007

In this paper, we develop a speech recognition system using a throat microphone. The use of this kind of microphone minimizes the impact of environmental noise. However, because of the absence of high frequencies and the partially loss of formant frequencies, previous systems developed with those devices have shown a lower recognition rate than systems which use standard microphone signals. This problem has led to researchers using throat microphone signals as supplementary data sources supporting standard microphone signals. In this paper, we present a high performance ASR system which we developed using only a throat microphone by taking advantage of Korean Phonological Feature Theory and a detailed throat signal analysis. Analyzing the spectrum and the result of FFT of the throat microphone signal, we find that the conventional MFCC feature vector that uses a critical pass filter does not characterize the throat microphone signals well. We also describe the conditions of the feature extraction algorithm which make it best suited for throat microphone signal analysis. The conditions involve (1) a sensitive band-pass filter and (2) use of feature vector which is suitable for voice/non-voice classification. We experimentally show that the ZCPA algorithm designed to meet these conditions improves the recognizer's performance by approximately 16%. And we find that an additional noise-canceling algorithm such as RAST A results in 2% more performance improvement.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.6
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• pp.77-87
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• 2009

Potential risks of communicable disease outbreaks have significantly increased in the era of global society. However, contingency planning of local governments for communicable diseases is not prepared to the proper level in various governmental sectors of many countries. Human being has been remarkable advances in medical science and public health. However, Severe Acute Respiratory Syndrome (SARS) still remains as a very dangerous transmissible disease that has great potential to create catastrophic consequences of casualties. The SARS outbreak between November 2002 and July 2003 resulted in 8,096 known infected cases and 774 deaths with a mortality rate of 9.6% worldwide (WHO, 2004). It is regarded as one of the human health disasters. Since about sixty-six percent of total SARS cases in the world were reported in People's Republic of China, Korean tour industry was significantly affected as a neighboring country. The objective of this research is to investigate major factors of Korea entry data sets, and to analyze economic impacts of Korean tour business interruption due to the period of SARS outbreak with tourist cases of four countries: Japan, U.S.A., China, and Taiwan. Results from this research show the seasonal and long-term trends of entry data sets of four countries, and direct and indirect impacts of SARS to Korean tour industry.

• Analytical Science and Technology
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• v.27 no.5
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• pp.243-247
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• 2014

Formaldehyde is defined as carcinogen causing leukaemia, lymphoma or nasopharyngeal carcinoma at high level of exposure. Furniture-manufacturing workers can be exposed to formaldehyde, which implies serious impact on health of the workers. The authors carried out ambient monitoring of formaldehyde in the field, and identified the source of formaldehyde generated during the working process by testing the condition in the laboratory settings. After sampling formaldehyde in the air with 2,4-DNPH (2,4-dinitrophenylhydrazine) coated silica gel, we extracted formaldehyde derivative with acetonitrile and analyzed the extract using HPLC with UV detector at 360 nm. Formaldehyde was separated by ACQUITY UPLC BEH $C_{18}$ column at a flow rate of 0.5 mL/min using 45% acetonitrile as mobile phase. The workers were exposed to higher level of formaldehyde than normal air. Formaldehyde up to 0.31 ppm was detected in the process of veneer attachment, which exceeded 0.3 ppm, the ceiling value of ACGIH standard. The laboratory test of measuring formaldehyde generated from the glue and veneer used in the attachment process resulted in more formaldehyde generation as the temperature increased, and more from the veneer. Heating the veneer to $100-150^{\circ}C$ following the real condition of the manufacturing site generated 1.14-2.70 ppm of formaldehyde from the sample, which was 2-5 times higher level than Korean limit of exposure (0.5 ppm). As the workers handling and processing the veneer which was produced by wet process had high possibility to be exposed to formaldehyde, urgent improvement and management of working environment of furniture manufacturer is demanded.

• Applied Chemistry for Engineering
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• v.31 no.5
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• pp.514-519
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• 2020

Graphite materials for lithium ion battery anode materials are the most commercially available due to their structural stability and low price. Recently, research efforts have been conducted on carbon coatings by improving side reactions at the edge site of carbon materials. The carbon coating process has classified into a CVD by chemical reaction, wet coating process with solvent and dry coating by mechanical impact. In this paper, the rapid crush/coating process was used to solve the problem of which only few parts of the carbon precursor (pitch) can be used and also environmental problems caused by solvent removal in the wet coating process. When the ratio of needle coke to pitch was 8 : 2 wt%, and the rapid crush/coating process was carried out, it was confirmed that the fracture surface was coated by pitch. The pitch-coated sample was treated at 2400 ℃ and 41.8% improvement in 10C/0.1C rate characteristic was observed. It is considered that the material simply manufactured through the simple crush/coating process can be used as an anode electrode material for a lithium ion battery.

• The Journal of Korean Medicine
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• v.24 no.3
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• pp.51-64
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• 2003

Objective : This study investigated the alteration of neural activity and effect of Yanggyuksanhwa-tang (Lianggesanhuo-tang) on cerebral ischemia of rats. Methods : Considering age-related impact on cerebral ischemia, aged rats (18 months old) were used for this study. Ischemic damage was induced by the transient occlusion of bilateral common carotid arteries (BCAO) with hypotension. Yanggyuksanhwa-tang (Lianggesanhuo-tang) was administered twice a day orally. Then alterations of neural activities in the brain of aged BCAO rats were measured by the [$^{14}C$]2-deoxyglucose autoradiography method. Results : The BCAO in aged rats led to significant decrease of neural activity in the whole brain. Treatment with Yanggyuksanhwa-tang (Lianggesanhuo-tang) significantly attenuated the decrease of neural activity in the whole brain following BCAO ischemia. Treatment significantly attenuated the decrease of neural activity in the CA1, CA2, CA3, dentate gyrus of the hippocampus, activated barrel, barrel cortex, somatosensory cortex, cingulate cortex, caudate putamen, and medial septal nucleus following BCAO in aged rats. Treatment with Yanggyuksanhwa-tang (Lianggesanhuo-tang) also significantly attenuated the decrease of neural activity in the anteroventral thalamic nucleus, ventral anterior thalamic nucleus, arcuate nucleus, posterior hypothalamic area, medial mammillary nucleus, lateral periaqueductal gray, dorsal raphe nucleus, interpeduncular nucleus, median raphe nucleus, and medial pontine nucleus. Conclusion : It can be suggested that Yanggyuksanhwa-tang (Lianggesanhuo-tang) has a neuroprotecuve effect on cerebral ischemia through the control of glucose metabolic rate and cerebral blood flow.

• Journal of Gastric Cancer
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• v.14 no.1
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• pp.15-22
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• 2014

Purpose: To evaluate the prevalence of esophageal reflux-induced symptoms after gastrectomy owing to gastric cancer and assess the relationship between esophageal reflux-induced symptoms and quality of life. Materials and Methods: From January 2012 to May 2012, 332 patients were enrolled in this cross-sectional study. The patients had a history of curative resection for gastric cancer at least 6 months previously without recurrence, other malignancy, or ongoing chemotherapy. Esophageal reflux-induced symptoms were evaluated with the GerdQ questionnaire. The quality of life was evaluated with the European Organization for Research and Treatment QLQ-C30 and STO22 questionnaires. Results: Of the 332 patients, 275 had undergone subtotal gastrectomy and 57 had undergone total gastrectomy. The number of GerdQ(+) patients was 58 (21.1%) after subtotal gastrectomy, and 7 (12.3%) after total gastrectomy (P=0.127). GerdQ(+) patients showed significantly worse scores compared to those for GerdQ(-) patients in nearly all functional and symptom QLQ-C30 scales, with the difference in the mean score of global health status/quality of life and diarrhea symptoms being higher than in the minimal important difference. Additionally, in the QLQ STO22, GerdQ(+) patients had significantly worse scores in every symptom scale. The GerdQ score was negatively correlated with the global quality of life score (r=-0.170, P=0.002). Conclusions: Esophageal reflux-induced symptoms may develop at a similar rate or more frequently after subtotal gastrectomy compared to that after total gastrectomy, and decrease quality of life in gastric cancer patients. To improve quality of life after gastrectomy, new strategies are required to prevent or reduce esophageal reflux.

• Sleep Medicine and Psychophysiology
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• v.5 no.2
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• pp.119-133
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• 1998

Attentional processes facilitate cognitive and behavioral performance in several ways. Attention serves to reduce the amount of information to receive. Attention enables humans to direct themselves to appropriate aspects of external environmental events and internal operations. Attention facilitates the selection of salient information and the allocation of cognitive processing appropriate to that information. Attention is not a unitary process that can be localized to a single neuroanatomical region. Before the cortical registration of sensory information, activation of important subcortical structures occurs, which is called as an orienting response. Once sensory information reaches the sensory cortex, a large number of perceptual processes occur, which provide various levels of perceptual resolution of the critical features of the stimuli. After this preattentional processing, information is integrated within higher cortical(heteromodal) systems in inferior parietal and temporal lobes. At this stage, the processing characteristics can be modified, and the biases of the system have a direct impact on attentional selection. Information flow has been traced through sensory analysis to a processing stage that enables the new information to be focused and modified in relation to preexisting biases. The limbic and paralimbic system play significant roles in modulating attentional response. It is labeled with affective salience and is integrated according to ongoing pressures from the motivational drive system of the hypothalamus. The salience of information greatly influences the allocation of attention. The frontal lobe operate response selection system with a reciprocal interaction with both the attention system of the parietal lobe and the limbic system. In this attentional process, the search with the spatial field is organized and a sequence of attentional responses is generated. Affective, motivational and appectitive impulses from limbic system and hypothalamus trigger response intention, preparation, planning, initiation and control of frontal lobe on this process. The reticular system, which produces ascending activation, catalyzes the overall system and increases attentional capacity. Also additional energetic pressures are created by the hypothalamus. As psychophysiological measurement, skin conductance, pupil diameter, muscle tension, heart rate, alpha wave of EEG can be used. Event related potentials also provide physiological evidence of attention during information process. NI component appears to be an electrophysiological index of selective attention. P3 response is developed during the attention related to stimulus discrimination, evaluation and response.