• ALGAE
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• v.20 no.3
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• pp.207-216
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• 2005

Myrionecta rubra, a mixotrophic ciliate, is a cosmopolitan red tide species which is commonly found in neritic and estuarine waters. M. rubra had long been listed as an “nculturable protist”until 2 different laboratory strains were finally established in 2 research groups at the beginning of this century, enabling us to perform initiative investigation into various aspect of the live M. rubra strains (Gustafson et al. 2000; Yih et al. 2004b; Johnson and Stoecker 2005). Field sampling was carried out on high tide at 2 fixed stations around Kunsan Inner Harbor (St.1 near the Estuarine Weir and St.2 off Kunsan Ferry Station) every other day for 4 months from mid-February 2004 to understand detailed figure of the recurrent spring blooms of M. rubra following the onset of the water gates operation of the Keum River Estuarine Weir on August 1994. With its maximum abundance of 272 cells mL$^{-1}$ in St.1, fluctuation pattern of the M. rubra population at the 2 stations was strikingly similar. Notable growth of M. rubra population started on late April, to cause M. rubra red tides during one month from mid-May in which “xceptionally low salinity days”without its red tide were intermittently inserted. High abundance of M. rubra over 50 cells mL$^{-1}$ was recorded at samples with their water temperature and salinity higher than 15${^{\circ}C}$ and 4.0 psu, respectively. During pre-bloom period when salinity fluctuation is moderate and the water temperature is cooler than 15°C, Skeletonema costatum, a chain-forming centric diatom, was most dominant. Cyanobacterial species such as Aphanizomenon flos-aquae and Phormidium sp. replaced other dominant phytoplankters on the days with “xceptionally low salinity”even during the main blooming period of M. rubra. To summarize, M. rubra could form spring blooms in Keum River Estuary when the level of salinity fluctuation was more severe than that for the dominant diatom Skeletonema costatum and milder than that for the predominance by freshwater cyanobacteria. Therefore, optimal control of the scale and frequency of freshwater discharges might lead us to partially modify the fluctuation pattern of M. rubra populations as well as the period of spring blooms by M. rubra in Keum River Estuary. Sampling time interval of 2 days for the present study or daily sampling was concluded to be minimally required for the detailed exploration into the spring blooms by M. rubra populations in estuaries with weirs like Keum River Estuary.

• Journal of the Korean Applied Science and Technology
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• v.27 no.2
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• pp.137-143
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• 2010

Oxide semiconductors Thin-film transistors are an exemplified one owing to its excellent ambient stability and optical transparency. In particular zinc oxide (ZnO) has been reported because It has stability in air, a high electron mobility, transparency and low light sensitivity, compared to any other materials. For this reasons, ZnO TFTs have been studied actively. Furthermore, we expected that would be satisfy the demands of flexible display in new generation. In order to do that, ZnO TFTs must be fabricated that flexible substrate can sustain operating temperature. So, In this paper we have studied low-temperature process of zinc oxide(ZnO) thin-film transistors (TFTs) based on silicon nitride ($SiN_x$)/cross-linked poly-vinylphenol (C-PVP) as gate dielectric. TFTs based on oxide fabricated by Low-temperature process were similar to electrical characteristics in comparison to conventional TFTs. These results were in comparison to device with $SiN_x$/low-temperature C-PVP or $SiN_x$/conventional C-PVP. The ZnO TFTs fabricated by low-temperature process exhibited a field-effect mobility of $0.205\;cm^2/Vs$, a thresholdvoltage of 13.56 V and an on/off ratio of $5.73{\times}10^6$. As a result, We applied experimental for flexible PET substrate and showed that can be used to ZnO TFTs for flexible application.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.5
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• pp.1-13
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• 2017

Recently, due to worldwide industralization and urbanization, natural environment has been severly damaged and global warning is worsening. Heat wave, torrential rainfall, typhoon and other natural disasters continuously occur due to global warming. Policies such as carbon emission regulation are taken into effect to solve such problems. Such global trend has affected interest to natural ecosystem and developed as a concept of ecosystem-services. This study particularly focused on ground water storage capacity among various ecosystem-services such as climate control and soil formation. It is because Korea suffers from drought and flood every year. Therefore, this study aims to understand objective numerical value of ecosystem-services value regarding ground water storage capacity of biotop classes based on relationship among precipitation, amount of evapotranspiration, and runoff of 7 regions of Chilgok-gun, Gyeongsangbuk-do and to convert the value into economic value. The study calculated ground water storage capacity based on relationship among precipitation, amount of evapotranspiration, and run off. Calculated amount of each capacity was 29.26 million ton($30.2mm/m^2$), 430.46 million ton($140.4mm/m^2$), 11.30 million ton($150.1.0mm/m^2$), 33 milion ton($3.0mm/m^2$). Economical value of ecosystem-service by each biotop classes appeared 4,128,800 thousand KRW ($21.32KRW/m^2$) for agricultural biotop, and 60,403,600 thousand KRW ($98.52KRW/m^2$) for forest biotop, 1,572,800 thousand KRW ($104.4KRW/m^2$) for grassland biotop, and 47,600 thousand KRW ($2.18KRW/m^2$) for bare ground biotop. The result of this study like above, it will be used as important evidentiary material to preserve natural resource effectively from various development business and policies that damages natural eco-system. Also, it is judged that ecosystem-service value by each land coverage will be used as important material for preparing legalistic institution such as establishing natural environment preservation plan, budget for alternative forest resource creation cost.

• Korean Journal of Medicinal Crop Science
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• v.20 no.2
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• pp.124-128
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• 2012

When ginseng seedlings are cultured in paddy fields, quality degradation and yield reduction are induced by severe plant loss with chlorosis on leaves occurred physiological disorder by excessive salt and poor drainage, rusty-root occurrence, and root rot etc. Accordingly, in order to solve these problems, this study was performed to investigate the treatment method, concentrations and time of activated ion calcium as environment-friendly agricultural materials. Activated ion calcium is an enriched and purified water-soluble mineral calcium component for absorbing quickly into plant as a highly functional calcium and it is an alkaline calcium of 37% (370 $m{\ell}$/1 ${\ell}$) concentration with pH 13. Treatment method was that ginseng seeds were sown after removing water in the shade after seed immersion for 1 minute with active ion calcium of 20-fold diluted solution, and then irrigated $4{\ell}$ per 3.3 $m^2$ with 200-fold, 400-fold, and 600-fold diluted solution before emergence on late March, and supplied 1 time on leaves with 500-fold diluted solution in June and July respectively. The disease rate by treatment of activated ion calcium was that on the treatment of soil irrigated with 200-fold diluted solution compared to non-treated soil, damping-off was 33%, anthracnose was 100% reduced and the occurrence rate of rusty-root was 30% reduced. In addition, when active ion calcium of 200-fold diluted solution were soil irrigated, first and second grade ginseng were respectively 26% and 22% produced more, compared with control.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.307-312
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• 1989

Internal mass transfer during osmotic dehydration of carrots in sugar solutions was examined as a function of concentration, temperature and immersion time of those solutions using moisture loss, sugar gain, molality and rate parameter. Influence of osmotic dehydration and blanching on browning reaction of vacuum dried carrots(3% MC: wet basis) was also evaluated. Increasing the concentration and temperature of sugar solutions increased moisture loss, sugar gain, molality and rate parameter. Water loss and sugar gain were rapid in first 4 min and then levelled off. The rate of sugar gain and molality changes on temperature was significant in lower concentration$(20^{\circ}\;Brix)$ compared to higher concentration$(60^{\circ}\;Brix)$. The changes of rate parameter were affected by concentration than by temperature of sugar solutions. Moisture loss during osmotic dehydration using a sugar solution $(60^{\circ}\;Brix,\;80^{\circ}C)$ with 20min immersion time was 55.7%. Effect of osmotic dehydration and blanching before vacuum dried to 3% MC(Wet basis) on browning reaction was significant. Minimum browning reaction during vacuum drying was carried out using pretreatments such as osmotic dehydration in sugar solution$(40^{\circ}\;Brix,\;80^{\circ}C)$ with 16 min immersion time(O.D.=0.09) and blanching with 12 min immersion time at $80^{\circ}C$(O.D.=0.31) compared to control(O.D.=1.59).

• Tuberculosis and Respiratory Diseases
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• v.43 no.1
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• pp.69-74
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• 1996

Background: The diagnosis of pulmonary embolism (PE) based on clinical findings is often elusive and therefore requires confirmative diagnostic method. Pulmonary angiography, though the gold standard for the diagnosis of pulmonary embolism, is an invasive method and requires trained personnel and special equipment. Lung V/Q scan, on the other hand, is a noninvasive method but the diagnostic specificity and sensitivity arc not satisfactory in case that the results are either intermediate or low probability scan. Plasma D-dimer is generated when a thrombus is fibrinolysed by plasmin and is known to be increased in various thrombotic disorders. The aim of this study was to investigate the value of the determination of plasma D-dimer level in the diagnosis of pulmonary embolism. Methods: Pulmonary angiography was performed in 17 patients who were clinically suspected to have pulmonary embolism. 9 patients(PE, $56{\pm}13.4$ yrs, M:F=8:1) were diagnosed to have pulmonary embolism by pulmonary angiography. The control group were the 8 patients with negative pulmonary angiography and 13 orthopedic patients with no evidence of pulmonary embolism on scintigraphic and impedance plethysmographic studies(n=21) (non-PE, $54.5{\pm}11.1$ yrs, M:F=11:10). Plasma D-dimer was measured by latex agglutination method in study subjects and the results were analyzed according to the presence or absence of pulmonary embolism. Results: 1) The increased level of plasma D-dimer was more frequently observed in the patients with pulmonary embolism than in the controls(>0.5 mg/L, 8 in PE, 10 in non-PE; <0.5 mg/L, 1 in PE, 11 in non-PE, p=0.049). 2) The diagnostic value of plasma D-dimer level higher than 0.5 mg/L were as follows: sensitivity 88.9%(8/9), specificity 52.4%(11/21), positive predictive value 44.4%(8/18), and negative predictive value 91.7%(11/12). Conclusion: Plasma D-dimer determination showed high sensitivity and negative predictive value in the diagnosis of pulmonary embolism and is therefore thought to be useful in excluding the possibility of pulmonary embolism.

• The Korean Journal of Community Living Science
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• v.19 no.3
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• pp.353-363
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• 2008

Recently some Korean feminists have reported the family management agreement (FMA) can contribute to enhance the women farmers' legal status and to improve their farm management. The FMA is a formal document written each rights and responsibilities on the farm management, income allocation, and labor condition such as working time and work-off days agreed among family members. Since 2004, 161 farmer couples have signed and practiced the FMA after two-day workshop scheduled for the agreement. The purpose of this study is to analyze the effects of FMA on the increase of participation in (am management among women farmers. Data were collected from 204 FMA couples through the structured questionnaires. Also interview and participating observation were carried out. Paired t-test were conducted using SPSS 12.0 for Windows program. Major findings were as follows. Women farmers' participation in decision making of farming activities has significantly increased after than before the FMA. However, husbands' participation in decision making is higher than women farmers even after the FMA. After the FMA, labor compensation, regularly or irregularly, for women farmers has increased to 53.3%, 35.3% higher than 18% of the previous study and women farmers' ownership of their farm assets has increased to 48.1% from 29.1%. Also, there is a tendency women farmers' role as a representative of their farm has increased. In conclusion the FMA makes women farmers participate more in farm management as decision maker, income beneficiary, farm asset owner, and farm representative, which encourage them to get the legal status as a farmer and to control their farm management risk. It is suggested that the FMA be selected as a program in order to strengthen the agricultural competitiveness.

• Korean Security Journal
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• no.50
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• pp.307-337
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• 2017

The freedom of assembly is the fundamental freedoms guaranteed by the Constitution. However, as far as our reality is concerned, the freedom of assembly is guaranteed only when it is under the control of the police, and otherwise it is perceived as an object to be suppressed. Police say even that they will not tolerate even a small illegal law while referring to the "broken window theory". Therefore, regardless of the peaceful nature of the rally, it is too obsessed with 'compliance'. This attitude is causing the citizens who participated in the assembly to be put to the object to be suppressed. This paper analyzes the requirements and current status of police force, focusing on the vehicle-wall-blocking and water cannon as a means of using the police force, which is a recent problem, and suggests ways to improve it. First of all, the installation of the wall cuts off the essential communication function of the assembly by separating the meeting place from the object of protest. Thus, despite the warning for prevention in the face of illegal acts, other than installing a barrier, it should be allowed only in the 'urgent case where there is a risk of causing damage to the life, body or property of the person'. Without this urgency, the vehicle-wall-blocking should not be allowed to be proactive as well as preventive. Secondly, the water cannon is a police force that is likely to harm people's life and body. Therefore, aiming shots, which could pose a significant risk to the human body, should in principle be prohibited. However, considering its risk, it should be supplementary used only when there is no other alternative, only when the direct risk to the legal interest of the other person or the order of public well-being is 'obvious'. In addition, as for the use standard of such a thing, it is necessary to be specified by law.

• Korean Journal of Materials Research
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• v.22 no.9
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• pp.476-481
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• 2012

Among the various roll-to-roll printing technologies such as gravure, gravure-offset, and reverse offset printing, reverse offset printing has the advantage of fine patterning, with less than 5 ${\mu}m$ line width. However, it involves complex processes, consisting of 1) the coating process, 2) the off process, 3) the patterning process, and 4) the set process of the ink. Each process demands various ink properties, including viscosity, surface tension, stickiness, and adhesion with substrate or clich$\acute{e}$; these properties are critical factors for the printing quality of fine patterning. In this study, Ag nano ink was developed for reverse offset printing and the effect of polyvinylpyrrolidone(PVP), used as a capping agent of Ag nano particles, on the printing quality was investigated. Ag nano particles with a diameter of ~60 nm were synthesized using the conventional polyol synthesis process. Ethanol and ethylene glycol monopropyl ether(EGPE) were used together as the main solvent in order to control the drying and absorption of the solvents during the printing process. The rheological behavior, especially ink adhesion and stickiness, was controlled with washing processes that have an effect on the offset process and that played a critical role in the fine patterning. The electrical and thermal behaviors were analyzed according to the content of PVP in the Ag ink. Finally, an Ag mesh pattern with a line width of 10 ${\mu}m$ was printed using reverse offset printing; this printing showed an electrical resistivity of 36 ${\mu}{\Omega}{\cdot}cm$ after sintering at $200^{\circ}C$.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.3
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• pp.215-226
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• 2015

In this study, with variables the cross section area ($97m^2$, $58m^2$, $38m^2$) and the wind velocity(0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5 m/s), the time of getting off train dependent on the way of itself and the width of the evacuation route was analyzed, and also fire and evacuation characteristics is reviewed by cross section area of each wind velocity. As the result, if cross section become smaller, the density of harmful gases in the tunnel increased more than the ratio of decreasing cross section area. In the case of small cross sectional area, the surrounding environment from initial fire is indicated to exceed the limit criteria suggested in performance based design. In the analysis of effective evacuation time for evacuation characteristics, the effective evacuation time was the shortest in the case of evaluating effective evacuation time by the visibility. Also, there was significant difference between the effective evacuation time on the basis of performance based evaluation and the effective evacuation time obtained by analyzing FED (Fractional effective dose), one of the analysis method obtaining the point that deaths occur, against harmful gases.