• Journal of Korea Water Resources Association
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• v.39 no.10 s.171
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• pp.881-890
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• 2006

Hydrological characteristics and urbanization effects in the Gap river catchment were investigated employing the SWAT model. The hydrological characteristics analysis showed that total runoff in the whole catchment from 2001 to 2004 consists of 44% of groundwater flow, 6% of lateral flow and 50% of surface flow under year 2000 landuse conditions. The analysis of urbanization effect using different landuse maps for year 1975 and 2000 indicated that although 5% increase in urbanized areas did not significantly impact on the total runoff in the whole catchment, a sub-basin where urbanized area increased by 32% over the past 30 years showed $68{\sim}73%$ decrease in groundwater flow and $22{\sim}66%$ increase in surface flow. It was found that urbanization decreased overall soil moisture and percolation rate except for some increase in soil moisture during dry season. Urbanization effect was found more sensitive during a dry year which has less rainfall and higher evapotranspiration than during a wet year. Therefore, from the results of this study we could infer increased flood damage during wet season and dried stream during dry season due to urbanization. To conclude, the results of this study can provide fundamental information to the eco-friendly restoration project for the three major rivers (Gap-cheon, Yudeung-cheon and Daejeon-cheon) in Daejeon Metropolitan City.

• Journal of Wetlands Research
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• v.20 no.2
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• pp.181-189
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• 2018

This study was performed to analyze the dynamics and distributional condition of biological community and to support the basic information about the estuarine ecosystem management by using the intensively surveyed results by each taxon experts around Tamjin river. We analyzed the biological diversity, abundance, correlation among species, and ecological characteristics about 11 taxa groups including vegetation, fish, birds, mammals, etc. in the Tamjin river estuarine ecosystem. We classified vegetation types into 7 physiognomic types and 18 communities according to habitat conditions with the physical environments and salinity. In total, 1125 species including 9 species of endangered species were identified in research area. The species composition and distributional characteristics of each taxon were corresponded to the environmental characteristics of the estuarine ecosystem. Especially, the species diversity and distribution were clearly distinguished in the river according to the difference of the environmental factors such as flow rate, salinity, and soil. Despite the disturbance factors such as barrage and levees, the biodiversity and its distribution were evaluated to be high level under the current environmental conditions. However, loss or reduction of wildlife habitat due to reclamation, embankment, barrage installation and expansion of farmland has been identified as a major threat to the diversity and health of the local ecosystem. The results of this study can be used as a basic data to cope with various development pressure and damage crisis of the whole estuaries including Tamjin river.

• Fire Science and Engineering
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• v.30 no.1
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• pp.104-110
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• 2016

Positive displacement pumps with high pressure and water capacity are used large fires in various high-rise buildings. This study provides information for a performance approval standard of fire pumps for fire trucks based on centrifugal pump standards enacted in 2012. An experiment was conducted with a positive displacement pump for three levels of performance from the approval standard (V-1, 2, and 3). The efficiency of the pump was included in the reference, which requires the approval of 65% performance, the same as a centrifugal pump. The water pressure is between 1.5 and 2.5 MPa, and the required flow rate was established as at least $0.31m^3/min$ and up to $3.0m^3/min$. A relief valve was added to adjust the shut-off pressure due to the structural characteristics of the positive displacement pump. A strainer was also installed to prevent damage to the inside of the pump due to foreign matter. However, the strainer includes a difference from the positive displacement pump to operate without a vacuum pump and the centrifugal pump. This is due to the additional approval standard portion of the positive displacement pump, which is expected to be selected for more variety of fire-fighting equipment and proactive responses to fire suppression in a high-rise buildings and large fires. In conclusion, this approval standard was enacted in January 2016.

• Environmental and Resource Economics Review
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• v.24 no.1
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• pp.1-53
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• 2015

In environmental policy areas, a greater use of economic instruments (EIs) has recently been observed in many countries. However, EIs are heterogeneous policy tools. The textbook case of a Pigouvian tax is far from widely used, mainly due to the information requirements and other structural and institutional constraints. The successful implementation of EIs might heavily depend on pre-existing structural and institutional conditions. Moreover, these institutional conditions are particularly unfavorable in developing countries. Using a simple analytical general equilibrium model, this paper examines how these constraints affect the welfare gain from the introduction of environmental taxes in developing countries. First, this paper solves for the second-best optimal Pigouvian tax and output tax in the presence of a distortionary tax on market use of labor. The result confirms that an environmental output tax achieves a socially-efficient level of emissions in the least-cost manner only if the nature of the linkage between the tax base and the environmental damage is fixed. Second, incorporating structural and institutional constraints into the model through a set of parameter values from China and the US, this paper calculates the net welfare effects of either using the ideal Pigouvian tax or instead using an output tax. The numerical simulation results show that the net welfare gain from the use of an ideal Pigouvian tax could be more than six times larger than that of an output tax in developing countries. On the other hand, the welfare gain is only 50 percent in developed countries. This means that the potential welfare disadvantage from using output taxes instead emissions tax for environmental purposes could be much greater in the case of developing countries.

• Journal of Conservation Science
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• v.33 no.5
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• pp.355-362
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• 2017

The Nongso tomb of Sunchang was built in a relatively deep place; hence there was little damage from grave robbers. The tomb was completely filled with a large amount of charcoal, and therefore the wooden coffin was excavated in relatively good condition. On the basis of the structure of the tombs, excavated artifacts, and radiocarbon dating results, the tomb is estimated to be from between the late Goryeo and the early Joseon period. The wooden coffin excavated is double-layered structures consisting of an outer coffin and an inner coffin. The outside of the wooden coffin is thickly lacquered and decorated with yellow letters and white motifs. An analysis of the pigments' components revealed that the major component of the letters was gold (Au) and the major component of the motifs was silver (Ag). The coffin lacquer had three layers: a pigment layer, a yellowish-brown layer, and a black layer. The wooden bases of the coffins were painted with a black substance, such as soot, as mineral elements were not detected in the black layer. The yellowish-brown layer is presumed to be refined lacquer. From the analysis of the structure of the layers and pigments, we can estimate the method was adopted for making lacquer for wooden coffin. It is assumed that the method used gold leaf and gold powder. The form of the pigment and the internal structure are likely to be gold leaf, but the shape of the surface letters appears to have been formed using gold powder. This study will serve as important information for understanding lacquer making techniques at the time of the tombs' construction by confirming the making method through reproduction experiments using gold leaf and gold powder.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.4
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• pp.294-302
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• 2019

As a series of fundamental researches on the development of an automatic identification monitoring system for fishing gear. Firstly, the study on the installation method of automated identification buoy for the coastal improvement net fishing net with many loss problems on the west coast was carried out. Secondly, the study was conducted find out how to install an automatic identification buoy for coastal gill net which has the highest loss rate among the fisheries. GPS for fishing was used six times in the coastal waters around Seogwipo city in Jeju Island to determine the developmental status and underwater behavior to conduct a field survey. Next, a questionnaire was administered in parallel on the type of loss and the quantity and location of fishing gear to be developed and the water transmitter. In the field experiment, the data collection was possible from a minimum of 13 hours, ten minutes to a maximum of 20 hours and ten minutes using GPS, identifying the development status and underwater behavior of the coastal gillnet fishing gear. The result of the survey showed that the loss of coastal net fishing gear was in the following order: net (27.3%), full fishing gear (24.2%), buoys, and anchors (18.2%). The causes were active algae (50.0%), fish catches (33.3%) and natural disasters (12.5%). To solve this problem, the installation method is to attach one and two electronic buoys to top of each end of the fishing gear, and one underwater transmitter at both ends of the float line connected to the anchor. By identifying and managing abnormal conditions such as damage or loss of fishing gear due to external factors such as potent algae and cutting of fishing gear, loss of fishing gear can be reduced. If the lost fishing gear is found, it will be efficiently collected.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.26 no.1
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• pp.25-33
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• 2015

Background and Objectives:The objective of this study was to investigate the features of post-thyroidectomy subjective voice disorder by Voice Handicap Index (VHI) and Voice Symptom Scale (VOISS) through aerodynamic analysis and to investigate the appropriate voice therapy intervention. Materials and Methods:Twenty post-thyroidectomy patients who had no recurrent laryngeal nerve paralysis through laryngeal stroboscopy were enrolled for this study. Acoustic and aerodynamic evaluations were performed before operation, 2 weeks and 3 months after operation. Subjective voice evaluation was performed by VHI and VOISS. Aerodynamic evaluation was compared and analysed by maximum phonation time(MPT), phonation threshold pressure(PTP), mean air flow rate(MFR), etc. Subjective voice evaluation was surveyed through VHI and VOISS. To evaluate patients' symptoms related to functional voice disorder, scores on physical domain in VHI and VOISS were selected to be compared for each session. Results: The 10 out of 20 participants who complained of voice symptoms had no significant difference with pre-operation in acoustic evaluation, but all showed higher scores on 2 weeks and 3 months after operation compared to pre-operation, in VHI-physical domain and selected questionnaires in VOISS. They reduced MPT and increased PTP value simultaneously. Laryngeal massage and breathing training were simultaneously treated to them, 5 participants resulting in improvement in MPT and PTP compared to pre-treatment. Conclusion:Patients who complained voice change with no organic damage after thyroidectomy were all shown to have reduced MPT and increased PTP in some by aerodynamic evaluations. Reduced MPT may imply some problem in air flow beneath glottis. Increased PTP suggests much more effort in vocalization mechanism than pre-operation. Comparing aerodynamic evaluations in post-thyroidectomy may provide information on behavioral interventions. Additionally, study on laryngeal massage and breathing training simultaneously treated to patients with such voice disorder is needed to be conducted with larger number of participants.

• Child Health Nursing Research
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• v.20 no.2
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• pp.113-122
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• 2014

Purpose: Purposes of this study were to identify the level of parental fever phobia and to investigate the relationship between level of parental concern about fever and related variables. Methods: Participants were 151 parents of children who visited a pediatric outpatient clinic. A selfreported structured questionnaire was used for data collection and data were analyzed using descriptive statistics and ${\chi}^2$-test. Results: Almost half of participants defined a minimum temperature for fever as $37.8^{\circ}C$ and a minimum temperature for high fever as $38.9^{\circ}C$. About 75% of participants identified harmful effects of fever as seizure and brain damage, were 'very worried' about fever, measured their child's temperature every hour or less, provided tepid massage and woke children to give antipyretics during febrile illness. There were significant relationships between level of parental concerns about fever and prior experience of febrile seizures, and/or being parents of a single child. Conclusion: Results indicate that fever phobia is prevalent among parents. Further studies are needed to develop and evaluate childhood fever management educational programs for parents. Considering health care providers as a primary information resource about fever management, health care providers should play a vital role to reduce parental unrealistic concerns about fever.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.12
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• pp.1239-1247
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• 2003

OFDM(orthogonal frequency division multiplexing) communications system is very attractive for the high data rate transmission in the frequency selective lading channel. Since OFDM has high PAPR(peak-to-average power ratio), OFDM signal may be distorted by the nonlinear HPA(high power amplifier). In this paper, we propose the DSI(dummy sequence insertion) method for OFDM communication system. Some sub-carriers are inserted for PAPR reduction. They carry the specified dummy data sequence which are used for only PAPR reduction and do not work as side information like the conventional PTS(partial transmit sequence) or SLM(selected mapping) method. We use the complementary sequence and the combination of the correlation sequence as the dummy sequence. Flipping technique is used for the DSI method to get the effective PAPR reduction. It is important that BER of the proposed method is independent of the damage of the dummy data sequence. And DSI method has better spectral efficiency than the conventional block coding. On the other hand, threshold PAPR method is applied to cut down the processing time. However, this DSI method is not better than the conventional PTS method in the respect of the PAPR reduction performance. The DSI method includes the threshold PAPR lower than the PAPR of the OFDM signal, reduces the processing time and improves the BER performance.

• Journal of Veterinary Clinics
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• v.26 no.3
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• pp.246-258
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• 2009

This study was conducted for behavioral characteristic analysis of the Asiatic Black Bear in a limited space. Behaviors of eight Asiatic Black Bears were classified into 13 normal stances and locomotor activities, 15 normal maintenance behaviors, 9 locomotory compulsive behaviors, 2 non-locomotory compulsive behaviors through the 3 years of monitoring. The bears had originally been released into the Jiri National Park for Asiatic Black Bear Restoration Project and were withdrawn again because of several reasons such as habituation to humans, and apiary damage. Through the monitoring of 6 hours per day during 3 months, classified behaviors were analyzed based on sex, age, observing month, observing timing, captivity period, and captive form. The total rate of stereotypic behaviors was $26.51{\pm}13.38%$. Among these, RA(Rest_A) was rated high as $47.32{\pm}18.32%$. In addition, SP(Standard pace), HR(Head rear), EP(Extended pace) were most frequently observed behaviors. The time budget of TFS(Two feet stand), SA(Sniff_A) and SB(Sniff_B) on females and younger individuals were relatively higher than male and older individuals. So we confirmed that females and younger individuals had more wariness and curiosity. As the period of captivity took longer, the rate of stereotypic behaviors was higher and more stereotypic behaviors were observed in the afternoon. At night, behaviors related with resting like Rest-A, Rest-B, Lying down, Lying on abdomen, Sitting were more frequently observed. We concluded that the captive state could affect the behaviors of Asiatic Black Bear and long term research should be necessary.