• Asian-Australasian Journal of Animal Sciences
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• v.11 no.4
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• pp.434-440
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• 1998

Seven hybrid lines of Leucaena leucocephala $\times$ L. diversifolia and two control lines of L. leucocephala were compared for their adaptation to acid-soils and tolerance to damage by the psyllid, Heteropsyla cubana, at four locations over two years in Peninsular Malaysia. Primary data on leaf composition and in vitro digestibility (nutrition variables) and secondary data on plant height, stem girth and psyllid damage (agronomy variables) were the measures of performance. Cluster solutions of the nine lines were different within locations, between locations and between years for nutrition and agronomy variables. Controls and hybrids did not cluster separately. Principal component scores of the nine lines gave rank orders which were different by location and by year. No performance trend could be detected between hybrids and controls. The conclusion is that nutritional and agronomic characteristics in Leucaena are independent, soil composition and weather did not consistently affect performance, and evidence is inconclusive as to the benefits of interspecific crossing with L. diversifolia.

• Earthquakes and Structures
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• v.20 no.3
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• pp.261-278
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• 2021

In the current work, a series of seismic analyses of one-storey asymmetrical reinforced concrete (R/C) framed buildings is accomplished while the effect of soil deformability on the structural response is investigated. A comparison is performed between the simplified elastic behavior of R/C elements according to the structural regulations' instructions to the possible non-linear behavior of R/C elements under actual circumstances. The target of the time history analyses is the elucidation of the Soil-Structure Interaction (SSI) effect in the seismic behavior of common R/C structures by examining the possible elastic or elastoplastic behavior of R/C sections because of the redistribution of the internal forces by employing a realistic damage index. The conclusions acquired from the presented elastic and elastoplastic analyses supply practical guidelines towards the safer design of structures.

• Journal of Forest and Environmental Science
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• v.26 no.3
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• pp.193-202
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• 2010

To analyze the effects of tree roots on the stability of damage slope, distributional and physical properties of five-year Pinus densiflora roots were investigated. In the composition of roots, the proportion of main root to lateral root was 1 to 9 in slope condition. Root tensile force was increased in accordance with increased proportion to diameter of Pinus densiflora roots. However, tensile strength was decreased in proportion to diameter of roots. Root shear strength showed that soil containing Pinus densiflora roots was higher than that of non-treated soils. This result shows that Pinus densiflora roots significantly stabilize the surface-soil rather than sub-soil in damage slopes.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.6
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• pp.1764-1782
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• 2015

The purpose of this study is to investigate the understanding on the acid-base, acid rain and soil acidification of the elementary students. The participants in the current study were 280 6th graders from a elementary school in Gyeongnam Province. A questionnaire consists of four categories: understanding of (a) acid-base basic knowledge, (b) acid rain and (c) soil acidification. (d) In addition, students were asked to comment about the introduction of the acid rain experiment in the science textbook. The results are as follows; First, the results regarding acid-base basic knowledge. They know the classification, characteristics, and properties of acid-based solutions well but they don't know the acid-base neutralization, examples using properties and application in real life. Second, the results regarding acid rain, students know the definition and damage of acid rain but they don't know the causing substances, emission source and way of solution of acid rain for lack of knowledge. Third, the results regarding soil acidification was the well-known part for the students because they had continued learning about the soil from the lesson of acid rain. Also, we looked into the difference in gender and region about the understanding of acid-base, acid rain and soil acidification. According to the gender of the data about the understanding of acid-base, acid rain and soil acidification, the percentage of correct answers of female was higher than male's. Also we expected that urban students were higher than rural students on the understanding of acid-base, acid rain and soil acidification, but the understanding of urban students were similar to rural students. Fourth, we got positive answers and negative answers to the introduction of acid rain experiment. Most of the positive opinion were I want to know a lot acid rain experiment", followed by "It is possible to prevent the risk of the damage and It seems to having fun and new order. Most of the negative opinion were Acid rain experiment may be difficult and complicated followed by Just a theory in the book is enough, Acid rain experiment were boring and not fun, Acid rain experiment is dangerous, There are many to study in this order.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.316-316
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• 2017

The objective of this study is to estimate quantitatively soil salinity and soil loss at upland soils in agriculture land region in Saemangeum reclaimed land on the south Korea coasts. Soil loss and soil salinity are the most critical problem at reclaimed tidal saline soil in Korea. The several thematic maps of research area such as land cover map, topographic and soil maps, together with tabular precipitation data used for soil erosion and soil salinity calculation. Meteorological data were measured directly as air temperature, wind speed, solar radiation, and precipitation. The experiment was conducted 2% sloped lysimeter ($5.0m{\times}20.0m$) with 14 treatments and it were separated by low salinity division (LSD) and high salinity division (HSD) install. The cation content in ground water increased during time course, but in the case of land surface water the content was variable, and $K^+$ was lower than that of $Na^+$ and $Mg^{2+}$. At the LSD under rainproof condition, the salinity was directly proportional to soil water content, but at the HSD the tendency was no reversed. In condition of rainproof, the amount of soil salinity was higher at the HSD than at the LSD. Positive correlation was obtained between the soil water content and available phosphorous content at the rainfall division, but there was no significance at the surface soil of the rainproof division. Sodium adsorption ratio and anion contents in soil were repressed in the order of vinyl-mulching > non-mulching > bare field. According to the result of analyzing soil loss, soil loss occurred in a vinyl-mulching, a non-mulching and a bare field in size order, and also approximately 11.2 ton/ha soil loss happened on the reclaimed land area. The average soil loss amount by the unit area takes place in a non-mulching and bare field a lot. Our results indicate that soluble salt control and soil erosion are critical at reclaimed tidal saline soil and the results can provide some useful information for deciding management plans to reduce soil loss and salt damage for stable crop production and diverse utilization or cultivation could be one of the management options to alleviate salt damage at reclaimed tidal saline soil in Korea.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.1
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• pp.1-11
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• 2017

In order to assess risk of high temperature damages about corn during reproduction stages in the future, we carried out analysis of climate change scenarios RCP (Representative Concentration Pathway) 4.5 and RCP8.5 distributed by KMA (Korea Meteorological Administration) in 2012. We established two indexes such as average of annual risk days of high temperature damage which express frequency and strengthen index of high temperature damage. As results of producing maps for 157 cities and counties about average of annual risk days of high temperature damage during total periods of scenarios, the risk of high temperature in RCP8.5 was evaluated to increase at all over nation except inland area of Gangwon province, while RCP4.5 showed similar to present, or little higher. The maps of annual risk days of high temperature damage with 10 years interval in RCP8.5 prospected that the risk for damaging corn growth would increase rapidly from 2030's. The largest risk of high temperature damage in the future of RCP8.5 was analyzed at Changnyeong county located east-south inland area in Kyeongnam province, while the smallest of risk counties were Pyeongchang, Taebaek, Inje, and Jeongseon. The prospect at 12 counties which is large to produce corn at present and contains large plains have been showed that there will be only a little increase of risk of high temperature at Goesan, Yangpyeong, Hongcheon, Seosan, and Mooju until 2060's. But considering strengthen index of high temperature damage, most regions analyzed would be prospected to increase rapidly after 2030's. To cope with high temperature damage of corn in the future, we should develop various practical technologies including breeding adapted varieties and controlling cultivation periods.

• Journal of Environmental Impact Assessment
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• v.15 no.6
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• pp.357-372
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• 2006

The excessive land activities in farming can cause soil erosion, inundation by a flood, and fallow. So far land evaluation has been analyzed using the land use limitation derived from the excessive land activities. This study was done for evaluating the agricultural fields by using 3 land use limitations, inundation potential, soil erodibility potential, and fallow potential. The study area is Ibang-myeon, Changnyeong-gun, Gyeongnam-province, Korea. A logistic regression model was applied to recognize the inundation potential by a flood in the Nakdong river basin. And potential soil erodibility index (PSEI) was derived from USLE model to analyze the soil erodibility potential. And a probability model from a logistic regression model was applied to detect the fallow potential. Therefore, we found 220.7ha for the 4th grade and 86.1ha for the 5th grade was analyzed as water damage potential. Large area near Nakdong river have problem to grow the rice due to the damage by water inundation. And 213.6ha for the 3rd grade and 103.3ha for 4th grade was detected as a result of the analysis of soil erosion potential. The soil erosion potential was high when within-field integrity of soil was not stable, or the kinetic energy was high or the slope length was long due to a steep slope of a specific land. And 869.1ha for 3rd grade, 174.9ha for 4th grade, and 110.6ha for 5th grade was detected to be distributed having the fallow potential. Especially, a village, having a steep mountain, had 249.5ha for the 3rd grade, which was 28.7% of total area showing the 3rd grade. Finally, Three villages, including An-ri, Geonam-ri, Songgok-ri, showed they had largest area of the suitable land in the study area. These villages had similar topographic condition where they were far from Nakdong river, and they had relatively higher elevation and flat lands.

• Journal of Korean Society of Forest Science
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• v.107 no.4
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• pp.478-485
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• 2018

The study was carried out to select natural environmental factors that affect damage to hiking paths and to provide directions for facility management of hiking paths by a logistic regression analysis. The study sites is a total of 123 sample sites that located in the Baekdudaegan Guropo-Gisaengnyeong hiking trails. The variables used in the analysis model included mountain trail damage, forest type, herb of soil and crown density obtained through a field survey and included slope, soil and rock exposure obtained through FGIS. A logistic regression analysis of 43 sites and 80 undeveloped sites, 4 elements were selected for slope, herb of soil, soil and rock exposure. The slope and the herb of soil were positively correlated and the exposure of rock was negative. Soil has shown a positive correlation with its low missile and high sand ratio Saturn. Therefore, the management of the mountain hiking paths facilities should be established and restored considering the slope, herb of soil, soil and rock exposure.

• Earthquakes and Structures
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• v.10 no.4
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• pp.849-865
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• 2016

Beside the invaluable advancements in constructing more secure buildings, the post-earthquake inspections have reported considerable damages. In other words, the modern buildings satisfactorily decrease fatalities but the monetary impacts still mostly remain an unsolved concern of the stakeholders, the insurance companies and society together. Therefore, the fundamental target of the researches shifted from current force-based seismic design regulations to the Performance-Based earthquake engineering (PBEE). At the moment, some probabilistic approaches, such as PEER framework have been developed to predict the performance of building at any desired hazard levels. These procedures are so time-consuming, to which many details are needed to be assigned. It causes their usage to be limited. On that account, developing more straightforward methods seems indispensable. The main objective of the present paper is to adapt an equivalent static method in different damage states. Consequently, constant damage spectrums corresponding to different limit states, soil types, ductility and fundamental periods are plotted and tri-linear formulas are proposed for further applications. Moreover, the sensitivity of outcomes to the employed hysteresis model, ductility, viscous damping and site soil type is investigated. Finally, a case study building with moment-resisting R.C. frame is evaluated based on the both of new and current methods to ensure applicability of the proposed method.

• Journal of People, Plants, and Environment
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• v.23 no.6
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• pp.625-636
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• 2020

Background and objects: Soil contamination caused by CaCl₂ that is used to deice slippery roads in winter is now recognized as one of the major causes of damage of roadside plants. The aim of this study is to identify the salt mitigation effects of planting Chrysanthemum zawadskii and using a soil conditioner. Methods: The study was conducted at the site where Pinus densiflora f. multicaulis was planted on the roadside between Konkuk University Sageori and Danwol Samgeori located in Chungju-si. We classified the soils collected from the field experimental site according to the degree of the damage caused by deicing agents and divided the site into six blocks of three 80 × 80 cm plots replicated by treatment type. Three selected plots were treated with loess-balls on the soil surface (high salinity with loess-balls, medium salinity with loess-balls, low salinity with loess-balls) and three were left as an untreated control (H = high salinity, M = medium salinity, L = low salinity). The soil properties were measured including pH, EC and exchangeable cations as well as the growth of Chrysanthemum zawadskiia. Results: In the results of soil analysis, pH before planting Chrysanthemum zawadskiia was 6.39-6.74 and in September, five months after planting, the acidity was reduced to 5.43-5.89. Electrical conductivity (EC) was measured to be H > M > L with the higher degree of damage by deicing agents. The analysis of deicing exchangeable cations showed that the content of Ca²⁺ of soils were significantly correlated to deicing exchangeable cations (Ca²⁺, Na⁺, Mg²⁺) in the shoot part of Chrysanthemum zawadskii. The loess-ball treatment showed a lower content of deicing exchangeable cations than the treatment where Chrysanthemum zawadskiia was planted. Conclusion: In this study, the use of a new system made of loess-balls is proposed as a soil conditioner to protect soils from the adverse effects of road deicing salts. These data suggest that treatment of soil conditioners and planting Chrysanthemum zawadskiia are effective in mitigation of salt stress on the soils damaged by deicing agents.