• Journal of Korean Society of Forest Science
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• v.109 no.2
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• pp.157-168
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• 2020

The sensitivity of forest soil to acidification in the Republic of Korea (ROK) was evaluated based on pH_H2O, cation exchange capacity (CEC), and base saturation (BS). Sensitivity to acidification was categorized into three grades: adequate level (AL, pH ≧ 4.2, CEC ≧ 15cmol/kg, BS ≧ 15%), caution level (CL, at least one indicator is below AL), and severe Level (SL, all three indicators are below AL). Soil samples were collected from the 65 stationary monitoring plots (40 × 40 ㎢), distributed throughout ROK. Only 19% of soil samples were classified as AL, while 66% and 15% were CL and SL, respectively. The median of pH_H2O, CEC, BS, and Ca/Al indicator in AL soils was pH 4.64, 20.7cmol/kg, 29%, and 6.3, respectively. Moreover, BC_ex (K⁺, Mg²⁺, Ca²⁺) and available phosphorus (AP) concentration compared with a threshold value and molar ratio of BC_ex and AP to total nitrogen (TN) was high. This indicates that AL soils have a good nutrient condition. The molar Ca/Al ratio, an indicator for toxicity of exchangeable aluminum (Al_ex), was more than 1, indicating no negative impact of Al_ex on plant growth. On the contrary, the median of pH_H2O, CEC, and BS in SL soils was pH 4.02, 13.2cmol/kg, and 10%, respectively. The Ca/Al index was less than 0.6, which indicates that negative impacts of Al_ex on plants were high. Furthermore, both the concentration of BC_ex in SL soils and the BC_ex/TN ratio were the lowest among the three acidity degrees. This shows that SLsoils can be degraded by soil acidification compared with less acidic soils.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.8 no.1
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• pp.193-203
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• 2013

The social welfare service is expanding to different field as the social welfare budget is increasing. By this opportunity, it needs to make clear of the basis of argument that the necessity of development of korean government's support and aid by social policy should be worked. Welfare economics perspective, this study used by the operating expenditure in welfare facilities for the elderly old people to effect social benefits to be gained, in other words, business value analysis. Local elderly people, provide opportunities to participate in the economic activities of the family welfare services offered to attainment of the elderly welfare policy, and provide disease prevention and health promotion opportunities, to enhance the satisfaction of life, including a wide range of impact will cause. In this study, elderly people use the welfare facilities for the elderly when they get the benefits by applying the AHP analysis techniques operating value was calculated. Elderly Welfare Center operated by the result of applying P senior welfare center Case of the metropolitan area value was estimated 248.4 billion won. Contribute to the effects caused by the cost factor of the analysis was 23.1% of the total 57.3 billion won. Independence elements 57.6 billion (23.2%), the analysis of the therapeutic elements 133.4 billion (53.7%) of the net was. The result of the study anticipates the role of basic research material for the necessity of intervention, support, and aid by the Welfare facilities for the elderly field at this point in time where the welfare budget policy in terms of universal social service is reinforced, rather than the trend, until recently, of realizing the Elderly welfare budget and service as Consumption expenditure and consumable benefits and the function of performing the effect and evaluation in tentative action of social conflict.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.1
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• pp.203-211
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• 2014

Tunnel reduces travel time as and it is essential facilities for the eco-friendly road construction. In recent years, It has been accelerating the tunnel construction to provide a higher level of traffic service but a driver driving in the narrow and dark tunnel takes characteristically psychological anxiety and the restriction of the sight. Moreover, A driver passing through more than 1,000m long tunnel, as to pass inside the monotonous form of the tunnel for a long time can cause drowsiness and increase the driver load. This driver load can degrade road-holding of the inside of the long tunnel highly and pose a high risk of accidents. Accordingly, In this study is to present the proper length of the Tunnel, considering the characteristics of traffic accident. For this, this study is that the long tunnel that affects traffic safety traffic safety variables are selected and classified. Traffic safety variables are classified in detail as a variable of the traffic accident and velocity one, the applicable variables the number of the traffic accident, the ratio of the traffic accident, driving velocity, the individual vehicle velocity etc. Traffic safety variables are categorized as more than a pole length of the tunnel in order to examine its impact on correlation analysis. The results indicate significant results in traffic accidents in accordance with traffic accidents, traffic safety, selects the variable was Variable depending on the length of the tunnel traffic safety point of significantly increasing the possibility of an accident can be seen as a high point. And the point of the Distribution of selected variables in order to create a traffic safety was a significant increase in traffic safety variables was set at critical intervals. Before reaching the critical point and the corresponding length of the long tunnel was set at the proper length. In this study, the optimum length of the proposed long tunnel through the long tunnel that occur in the future to contribute to reducing traffic accidents would be able to be determined.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.298-305
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• 2014

BACKGROUND: The utilization of green manures as alternatives to reduce the use of chemical fertilizers is considered a good agricultural practice. Effect of incorporation of green manure to soil on change of inorganic nitrogen (N) is well literatured. However, there have been few studies on examining entire dynamic of N including inorganic N and N gases in soil incorporated with green manure. The objective of this study was to examine the changes of inorganic N and N gases with single and mixture applications of hairy vetch and barley in the soil. METHODS AND RESULTS: Hairy vetch(H) and barley (B) were applied at the mixture ratio of B:H=0:0, B:H=100:0, B:H=0:100, and B:H=50:50 in soil. The soil-green manure mixtures were incubated in the dark at $25^{\circ}C$ for 17 weeks under aerobic conditions. Cumulative emission of $NH_3$ and $N_2O$ from soils amended with mixture of barley and hairy vetch(B:H=50:50) were less than those from amended with mono hairy vetch(B:H=0:100). Incorporation of single hairy vetch or mixture of barley and hair vetch application could significantly increased concentration of plant available N ($NH_4{^+}$) in early stage of plant growth and plant available N ($NO_3{^-}$) in later stage. However, high concentration of $NO_3{^-}$ in soil could cause adverse environmental impact through $NO_3{^-}$ leaching from soil. CONCLUSION: Conclusively, it might be a good soil management practice to incorporate mixture of barely and hairy vetch in the view point of increase in plant available N concentration and decrease in N losses through volatilization, denitrification, and leaching.

• Korean Journal of Environmental Agriculture
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• v.32 no.3
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• pp.224-230
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• 2013

BACKGROUND: Perchlorate(${ClO_4}^-$) is an anion that is extremely water-soluble and environmentally stable. It mostly exists in the form of sodium perchlorate, ammonium perchlorate and potassium perchlorate which are used in rocket fuels, propellants, ignitable sources, air bag inflation systems and explosives. Perchlorate can be taken into the thyroid glands and interfere with iodide uptake. The determination of perchlorate in agricultural products is important due to its potential health impact on humans. The objective of this study was to determine the perchlorate concentrations in the samples of various agricultural products and soils. METHODS AND RESULTS: In this study, samples of cereal(Rice, Barley, Corn, Bean), vegetable(Spinach, Lettuce, Sesame, Chives, Chili, Pumpkin, Tomato), fruit(Apple, Pear, Tangerine, Grape) were analyzed for perchlorate contents. Perchlorate concentrations were analyzed by liquid chromatography-tandem mass spectrometry. The results showed that agricultural products respectively contained perchlorate concentrations in the range of : cereals N.D.~$7.46{\mu}g/kg$, vegetables $0.52{\sim}23.06{\mu}g/kg$, fruits $0.19{\sim}2.66{\mu}g/kg$. Bioconcentration factor was in the order of : vegetables > cereals > fruits. Bioconcentration factor was highest follwed by Sesame 37.88, Corn 21.51, Spinach 10.57, Tangerine 4.39, Chives 2.89 and Lettuce 1.90. The recoveries of perchlorate from spiked agricultural products and soils ranged from 87.72~111.26% and 102.09~111.23%. CONCLUSION(S): The health risk assessment results obtained in this study are lower than the RfD(Reference Dose, 0.0007 mg/kg/body weight/day) value as suggested by the Integrated Risk Information System(US IRIS). Our results indicate that, people currently exposed to perchlorate from agricultural products consumption are considered as safe.

• Korean Journal of Environmental Biology
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• v.22 no.2
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• pp.247-258
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• 2004

Climatological, hydrological and planktonical research studies, measurements of primary production and photosynthetic efficiency from December 1976 to December 1978 have been carried out in two brackish lakes: Lake Etang de Berre and Lake Etang de Vaine located in the French Mediterranean coast, in the region of Carry-le-Rouet located on the north-west Mediterranean near Marseilles, and in fresh water inflows from 4 Rivers (Touloubre, Durance, Arc, Durancole) to Lake Etang de Berre. Physico-chemical parameters were measured for this study: water temperature, salinity, density, pH, alcalinity, dissolved oxygen (% saturation), phosphate, nitrate, nitrite, silicate etc. Diverse biological parameters were also studied: photosynthetic pigments, phaeopigments, specific composition and biomass of phytoplankton, primary pelagic production etc. Climatical factors were studied: air-temperature, solar-radiation, evaporation, direction (including strength) of winds, precipitation and freshwater volume of the four rivers. The changes in Lake ‘Etang de Berre’ ecosystem depend on the quality of the water in the Durance River, and on the effects of seawater near the entrance of the Caronte Canal. The water quality of the lake varies horizontally and vertically as a result of atmospheric phenomena, maritime currents and tides. The distribution of water temperatures is generally heterogeneous. Southeasterly winds and the Northeasterly Mistral wind are important in the origins of circulated and mixed water masses. These winds are both frequent and strong. They have, as a result, a great effect on the water environment of Lake Etang de Berre. In theory, the annual precipitation in this region is well over eight times the water mass of the lake. The water of the Durance River flows into Lake Etang de Berre through the EDF Canal, amounting to 90% of the precipitation. However, reduction of rainfall in dry seasons has a serious effect on the hydrological characteristics of the lake. The temperature in the winter is partially caused by the low temperature of fresh water, particularly that of the Durance River. The hydrological season of fresh and brackish water is about one month ahead of the hydrological season of sea water in its vicinity. The salinity of Lake Etang de Berre runs approximately 3$\textperthousand$, except at lower levels and near the entrance to the Caronte Canal. However, when the volume of the Durance River water is reduced in the summer and fall, the salinity rises to 15$\textperthousand$. In the lake, the ratio of fresh water to sea water is six to one (6:1). The large quantities of seston conveyed by rivers, particularly the Durance diversion, strongly reduce the transparency in the brackish waters. Although the amount of sunshine is also notable, transparency is slight because of the large amount of seston, carried chiefly by Tripton in the fresh water of the Durance River. Therefore, photosynthesis generally occurs only in the surface layer. The transparency progressively increases from freshwater to open seawater, as mineral particles sink to the bottom (about 1.7kg $m^{-2}a^{-1}$ on the average in brackish lakes). The concentration of dissolved oxygen and the rate of oxygen saturation in seawater (Carry-le-Rouet) ranged from 5.0 to 6.0 $m\ell$ㆍ.$1^{-1}$, and from 95 to 105%, respectively. The amount of dissolved oxygen in Etang de Berre oscillated between 2.9 and 268.3%. The monographs of phosphate, nitrate, nitrite and silicate were published as a part of a study on the ecology of phytoplankton in these environments. Horizontal and vertical distributions of these nutriments were studied in detail. The recent diversion of the Durance River into Lake Etang de Berre has effected a fundamental change in this formerly marine environment, which has had a great impact in its plankton populations. A total of 182 taxa were identified, including 111 Bacillariophyceae, 44 Chlorophyceae, and 15 Cyanophyceae. The most abundant species are small freshwater algae, mainly Chlorophyceae. The average density is about $10^{8}$ cells $1^{-1}$ in Lake Etang de Berre, and about double that amount in Lake Etang de Vaine. Differences in phytoplankton abundance and composition at the various stations or at various depths are slight. Cell biovolume V (equivalent to true biomass), plasma volume VP (‘useful’ biomass) and, simultaneously. the cell surface area S and S/V ratio through the measurement of cell dimensions were computed as the parameters of phytoplankton productivity and metabolism. Pigment concentrations are generally very high on account of phytoplankton blooms by Cyanophyceae, Chlorophyceae and Cryptophyceae. On the other hand, in freshwaters and marine waters, pigment concentrations are comparatively low and stable, showing slight annual variation. The variations of ATP concentration were closely related to those of chlorophyll a and phytoplankton blooms only in marine waters. The carbon uptake rates ranged between 38 and 1091 mg$Cm^{-2}d^{-1}$, with an average surface value of 256 mg; water-column carbon-uptake rates ranged between 240 and 2310 mg$Cm^{-2}d^{-1}$, with an average of 810, representing 290 mg$Cm^{-2}$, per year 45 000 tons per year of photosynthetized carbon for the whole lake. Gross photosynthetic production measured by the method of Ryther was studied over a 2-year period. The values obtained from marine water(Carry-le-Rouet) ranged from 23 to 2 337 mg$Cm^{-2}d^{-1}$, with a weighted average of 319, representing about 110 gCm$^{-2}$ per year. The values in brakish water (Etang de Berre) ranged from 14 to 1778 mg$Cm^{-2}d^{-1}$, with a weighted average of 682, representing 250 mg$Cm^{-2}$ per year and 38 400 tons per year of photosynthesized carbon for the whole lake.

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.251-257
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• 2011

Cobalt is a naturally occurring element found in rocks, soil, water and/or is among the harmful pollutants as generated by industrialized. In the environment, cobalt has two oxidation states, cobalt (II) (Co (II)) and cobalt (III) (Co (III)). If coastal water is contaminated by cobalt, it through the food chain can have an impact on marine ecosystems. Therefore, we examined the gametotoxic and embryotoxic effects of Co (II) at various concentrations (10, 100, 500, 1000, 2500 ppb) in the sea urchin $Hemicentrotus$ $pulcherrimus$. Spawning was induced by injecting 1 mL of 0.5 M KCl into coelomic cavity. Males released white or cream-colored sperms and females released yellow or orange-colored eggs. Experiment was begun within 30 min the collection of both gametes. The fertilization and embryo development rates test were performed for 10 min and 64 h after fertilization, respectively. The fertilization rates in the control condition (not including Co (II)) and experimental group were not significantly changed. The embryo development rates in the control condition were greater than 90% and were significantly decreased with concentration dependent manner. The normal embryogenesis rate was significantly inhibited in exposed to cobalt (II) ($EC_{50}$=71.84 ppb, 95% Cl=16.71-203.36 ppb). The NOEC and LOEC of normal embryogenesis rate were <10 ppb and 10 ppb, respectively. These results suggest that the early embryo stages of $H.$ $pulcherrimus$ have toxic effect at greater than 10 ppb of Co (II) concentration.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.12
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• pp.1761-1771
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• 2007

The artificial exaggeration of stage costumes is thought to be one of the major techniques of enhancing dramatic expression on stage, whichever for visual impact or symbolic effect of dramatization. In the history of stage dressing, a variety of styles has been tried using different materials and production techniques. This may be reviewed as an effort to express dramatic effects more effectively. As this trend became obvious in Europe after the Second World War, this study analyzes the stage costume to deepen our understandings of the role of costumes in expressing dramatic effects. To accomplish this, we first summarized the history of stage costume materials and technical advance and chose five major cases representing the history of stage costume since the Second World War in Europe based on aesthetic and creative aspects: 1) Simplified stage of Jacques Copeau, 2) Stylized stage of Bertolt Brecht, 3) Essential stage of Grotowski, 4) Measured stage of Robert Wilson the Master, and 5) Post-dramatic stage of Philippe $Decoufl\'{e}$. In each of particular case, the historical, material and dramatic contexts were examined as well as different material-effects. The results are as followings: 1) Costume for Copeau's simplified stage: its simplicity plays a supporting role to the gesture of actors(intensifying effect). 2) Costume for Brecht's stylized stage: the artificial stylization integrates into the play with the importance approximately equal to the actors's acting. 3) Costumes for Grotowski's essential stage: costumes disappeared to emphasize only actor's presence on stage. 4) Costumes for Robert Wilson's measured stage: costumes made concrete impression to the extent of obtaining the same importance of actor's body among other stage art elements(lighting, sound, props, actor, text, etc). 5) Costumes for Decoufle's post-dramatic stage: costumes in the era of multi technology possess multi functional aspects that surrogate actors' body. This study suggests that stage costumes take an important part in dramaturgy to the extent that the intent of dramaturgy can be induced enough from stage costume. Thus, costume makers are expected to incorporate the appropriate dramatic factor more than before.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.353-364
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• 2020

Recently in Korea, soybean harvesting has been delayed due to rainfall during the harvesting season, resulting in a reduction in yield and seed quality. This study was conducted to analyze the changes in yield and seed quality during delayed harvest with rainfall treatment using different harvesting methods, including field harvesting and polyethylene film covering after cutting fully-matured soybean plants (PE covering after cutting), with two major Korean soybean cultivars (Glycine max L), Pungsannamulkong and Daewonkong. The shattering rate of Pungsannamulkong, which is higher than that of Daewonkong, increased up to 41.8% when the harvest was delayed for 40 days without rainfall treatment by harvesting with PE covering after cutting. The weight of 100 seeds tended to decrease slightly as harvesting was delayed. When Daewonkong was harvested using the PE covering after cutting method with rainfall treatment, the yield decreased to the lowest level with a 0.8 kg ha^-1 daily reduction rate. Pungsannamulkong showed the lowest yield when harvested using PE covering after cutting without rainfall treatment with a 3.4 kg ha^-1 daily reduction rate. The infected seed rate increased according to the harvest delay in both cultivars, and significant differences were observed according to rainfall treatment and harvesting method. The germination rate was maintained above 95% even after 40 days of delayed harvest if there was no rainfall treatment. However, with rainfall treatment, the germination rate was significantly lowered as harvesting time was delayed. In the field harvesting with rainfall treatment, the germination rate decreased to 77.2% for Daewonkong and 76.5% for Pungsannamulkong after 40 days of harvest delay. For the 100-seed weight, effects of individual treatments and interactions between treatments were not observed. In contrast, the effect of interactions between treatments on the shattering rate was significant in both cultivars, indicating that the shattering rate had the greatest impact on the yield changes during delayed harvest.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.377-385
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• 2020

Recently, wheat consumption has been increasing in Korea, requiring increased production. Nitrogen fertilization is a critical determinant in crop yield; therefore, it is necessary to optimize the nitrogen fertilization regime with current trends that emphasize the minimum impact of nitrogen fertilizer on the environment. In this study, both nondestructive spectral analysis using a hyperspectral camera and growth analysis were performed to determine the optimal N top-dressing rates after heading. The nitrogen application regimes consisted of three conditions according to the secondary top-dressing rate: N_4:3:0 (0 kg 10 a^-1), N_4:3:3 (2.73 kg 10 a^-1), and N_4:3:6 (5.46 kg 10 a^-1). Subsequently, growth and physiological investigations were performed at the jointing, heading, and ripening stages of wheat, and spectral investigations were conducted. On April 29, as the nitrogen fertilization rate was increased to N_4:3:3 and N_4:3:6, plant height and grain yield increased by 4% and 8%, and 8% and 52%, respectively, compared to those under N_4:3:0. Leaf area index and SPAD value also increased by 13% and 24%, and 32% and 43%, respectively. The R (red), G (green), and B (blue) of leaf color were lowered by 15, 11, and 4 in N_4:3:3 and 44, 34, and 18 in N_4:3:6, respectively, as compared to the control. Grain yield was the highest at high top-dressing (N_4:3:6), however, there was no difference between no top-dressing (N_4:3:0) and intermediat top-dressing (N_4:3:3). The reflectance analyzed using a hyperspectral camera showed a difference in the near-infrared (NIR) region on March 19, and on April 29, there was a difference both in the visible light region greater than 550 nm and the NIR region. Vegetation indices differed according to fertilization regime, except for the greenness index (GI). The results of this study showed that not only growth and physiological analysis but also spectral indices can be used to optimize the nitrogen top-dressing rate.