• Korean Journal of Soil Science and Fertilizer
• /
• v.48 no.3
• /
• pp.225-232
• /
• 2015

We evaluated the effect of mixed liquid fertilizer (MLF) on growth responses of plants and soil chemical properties. A pot experiment with red pepper (Capsicum annuum L.) using loam soil was conducted for 81 days in a temperature-controlled glasshouse, and four N fertilization treatments were laid out in a completely randomized design with three replicates: control (C), chemical fertilizer treatment (CF), and two rates (MLF-0.5 and MLF-1.0) of MLF treatment. Soils were periodically sampled and analyzed for pH, EC(Electrical Conductivity), total N, inorganic N and total C, and some growth characteristics of red peppers were measured. During the experimental periods, the pH of MLF soils was higher than that of CF soils. Soil EC increased right after application of CF or MLF, and the intial increase persisted in CF and MLF soils at the end of experiment. Soil total-N increased right after application of CF or MLF, and this initial increase persisted only in MLF-1.0 soils. Soil inorganic N content initially increased in CF or MLF-1.0 soils, but the initial increase disappeared in 56 days after transplanting. Soil total-C was maintained higher in MLF-1.0 soils and lower in CF soils than in control soils, and the intial increase in MLF-1.0 soils finally disappeared to the level of control soils. Plant height, dry weight of plant organs (shoots, roots and fruit), and the number, diameter and length of red pepper fruits were greatest in CF plants. On the other hand, the effect of MLF-application was different depending on the rate of application. However, no consistent effect of N treatments on some major elements of the organs of red peppers was observed. The amounts of N taken up by plants were 1.3 g for CF, 0.8 g for MLF-1.0, 0.5 g for MLF-0.5 and 0.4 g for control treatments. The results of this study showed that mixed liquid fertilizer (MLF) could appropriately serve as an alternative to chemical N fertilizer in red pepper cultivation.

• Therapeutic Science for Rehabilitation
• /
• v.9 no.4
• /
• pp.33-43
• /
• 2020

Objective: This study used a mixed methods analytical approach to analyze the level of depression in and quality of life of patients who had been exposure to Agent Orange. Methods: Data on the general characteristics, depression level, and the quality of life of 29 patients who were hospitalized because of exposure to Agent Orange were collected. Focus group interviews were conducted with 17 of these 29 patients. Regarding mixed methods, the sequential integrated design model proposed by Teddlie and Tashakkori (2003) was employed. The analytical methods were as follows: (1) general characteristics were examined using frequencies and proportional distributions; (2) depression scores and quality of life scores were assessed using descriptive statistical analysis; and (3) content analysis was used to examine the focus group interview data. Results: The average K-GDS depression score was 19.24 points, and the average WHOQOL-BREF quality of life score was 57.66 points. The focus group interview data yielded 3 topics were named "deployment route", "the manner of exposure to Agent Orange", and "life after Agent Orange exposure". Conclusion: There is an urgent need to increase public awareness, develop a public policy response, and conduct additional research on ground occupational therapy programs that include physical therapy.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.14 no.3
• /
• pp.115-141
• /
• 2011

In urban space, public space is publicly or privately owned space freely accessible by the public. Privately owned public space to the public hosts small-scale rest facilities to serve the public in buildings of certain purposes and sizes for the sake of pleasant urban environment. The Building Act and building ordinances formulate a set of criteria for management and easement of construction standards as well as the area. When creating privately owned public space, one can get incentives through the easement of floor space index and height limit. The purposes of this study were to investigate and analyze privately owned public open space, which is freely accessible by the public, and its adjacent streets and to propose plans to improve the regulations for securing privately owned public space for more rational and practical legal applications. The study then proposed some plans to help to increase the quality of privately owned public space including applying the coefficient to suggest the type of privately owned public space fit for the features of the streets and measure the appropriate utility level differently and distinguishing the mandatory items according to the facility regulations in privately owned public space from the ones qualified for additional points in case of installation. The types of privately owned public open space should be applied differently and the content of facilities intended should be different according to whether it will serve as a resting place or grant more importance on traffic by walking, depending on the features of its adjacent streets. The privately owned public space, the frontage space of building, and the adjacent sidewalks should become a whole and be regarded as one space from the integrated perspective. The results of the study claim further significance in that it investigated privately owned open space and roadside across Seoul. They will serve as useful data to solve the problems with the privately owned public space of the city, which destroys spatial continuity by focusing on the quantitative increase of privately owned open space and creating individual privately owned open spaces and builds high-rise buildings alienated from the existing spaces, and to increase the quality of future privately owned public space.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.15 no.4
• /
• pp.119-132
• /
• 2012

The unmanaged abandoned concrete roads are vulnerable toward the issues on soil and water pollution, which requires flexible managing method such as eco-corridor after the process of ecological restoration. Among various alternations of abandoned concrete-paved roads, ecological restoration technique may be the most suitable method in sites including high quality of natural environment. Therefore, as in Young dong province, GyungBu express highway (227.24~229.04km), which is near to Hwang-gan IC, the survey to measure its effect of soil under the paving and water pollution by abandoned concrete roads was discussed. Then, the restoration method of plantings of landscape trees and hydro-seeding methods of artificial soil media was appraised through consecutive monitoring. The soil adequacy analysis shows lower percentage of heavy metal substance in each depth level compared to standard limit stated by the Ministry of Environment, along with low concerns raised after the analysis on heavy metal content of the spilled water on the concrete roads. Meanwhile, Korean Weigela (Weigela subsessilis L.H. Baily) was found to be withered in small-scale landscape trees planting sites. Among the seeding plants. the family of leguminosae, Silene armeria, Dendranthema boreale, Caryopteris incana and Aster yomena show good establishment results. Overall studies on planting of small and large landscape trees, planting method of container plants, planting method of ground cover plants, and germination and development trend of seeding plants of the experimental restoration site on abandoned concrete roads are revealing specific trends in the way landscape woody plants establishment and growth. Finally, this study suggests further studies and survey on varied plant restoration methods on abandoned concrete-roads for developed design guidelines of their methods.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.25 no.1
• /
• pp.1-6
• /
• 2005

With recent interest organic farming the use of legumes including vetch and clover to provide N to adjacent crops is increasing in Korea. In the present studies, we conducted a trial to investigate the effects of the application of N rate on nitrogen fixation and transfer from vetch to barley in mixed stands. The experiment was arranged in a randomized complete block design with three replications. Four different N rates(0, 75, 113 and 150/ha) was used and vetch+barley was broadcasted manually on 1.5 $\times$2 m plot in Oct. 2001. Half of urea and K$_{2}O, 200 Phosphate and 75 kg potash per ha were applied as basal dressing md half of N md 75 potash were used for topdressing to soil surface on MarctL 2002. The equivalent of 1kg ha$^{-1}$ at($^{15}$NH$_{4}$)$_{2}$SO$_{4}$ solution at 99.8 atom $\%$$^{15}$N excess was applied to the microplot in mid April. Forage was harvested from each plot at ground level and separated into barley and vetch. Total N content and It values of samples were determined using a continuous flow stable isotope ratio mass spectrometry(IsoPrime-EA. Micromass, UK.). The percentage of legume H fixed from atmospheric N2 were 95.0, 93.8, 94.4 and $84.8\%$ with increment of N levels. The percentage of N transfer from vetch to barley by N-difference method with increment of N fertilizer were from 58 to$49\%$ while 39 to $23\%$ in $^{15}$N-dilution method. The amount of transfer from vetch to barley were 87 to 68 kg/ ha with N level by N-difference moth여 and 58 to -56/ha with N application levels by $^{15}$N dilution method. The amount of nitrogen fixation per ha were from 150 kg / ha to 219 kg / ha by different method, but on the other side 49 to 105kg/ha by N$^{15}$-dilution.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.34 no.2
• /
• pp.81-86
• /
• 2014

This study was conducted to evaluate the effect of different seeding dates on agronomic characteristics, forage quality, dry matter (DM) and dry matter digestible (DDM) yields of sudangrass hybrid (Sorghum bicolor(L.) Moench) and oat (Avena sativaL.) at Seongju in Kyeongbuk from 2012 to 2013. The experiment was arranged in randomized complete block design with three replications. Sudangrass was seeded five times seeding dates of 10 days interval ranging from $1^{th}$ August to $10^{th}$ September in 2012 and 2013. Oat was seeded three times seeding dates of 10 days interval ranging from $20^{th}$ August to $10^{th}$ September in 2013. Sudangrass was harvested on $26^{th}$ October, 2012 and $2^{nd}$ November, 2013. Plant length and DM content decreased with delaying seeing date. The DM and DDM yields of sudangrass were higher (P<0.05) in first seeding date than all other seeding dates and decreased with delaying seeding dates (P<0.05). The DM and DDM yields of oat were higher (P<0.05) in first and second seeding dates than third seeding date. The results of this study indicated that early seeding of sudangrass would be a recommended than late seeding after $20^{th}$ of August, and late seeding of oat after $30^{th}$ August would be recommened for DM and DDM yields in the Southern Korea.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.5
• /
• pp.1838-1844
• /
• 2010

In distance education, contents are to convey what to learn to learners, and the efficient quality assurance of contents is the very first step to the enhancement of distance education. Most studies of the quality assurance of contents have mostly centered around the development of evaluation tools, and few studies have ever focused on analysis of the quality of contents itself, since it's not easy to do that due to difficulties in the selection of evaluatees or of contents to be analyzed. The purpose of this study was to analyze the quality of 58 distance education contents of on-the-job training and another training for the acquisition of qualifications. As a result, the contents of the learning contents segment ranked first. Among the components of each segment, there was room for improvement in the level of learning and learning elements in the learning contents segment. In terms of instructional design, the quality of interaction components should be taken to another level to boost the quality of contents in this segment. The findings of the study are expected to give some suggestions about which parts of contents should be improved in quality from a perspective of contents developers or suppliers to enhance the overall quality of contents.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.19 no.3
• /
• pp.83-91
• /
• 2015

Porous concrete consists of cement, water and coarse aggregate and has been used for the purpose of decreasing the earth environmental load such as air and water permeability, sound absorption, etc. However, the physical and mechanical properties of porous concrete changes due to compaction load during construction. For such a reason, the purpose of this study is to investigate the physical and mechanical properties of porous concrete according to the kinds of binder, the ratio of water to binder and target void ratio. In particular, this study has been carried out to investigate the influence of compaction load on the void ratio, strength and coefficient of permeability. Aggregate used in this study are by-products generated during production of crushed gravel with a maximum size of 13mm. The results of this study showed that the target void ratio, the coefficient of permeability and compressive strength of porous concrete had a close relationship with the void ratio, and it will be possible that the void ratio is suggested by the mix design of porous concrete. The compressive strength of porous concrete was the highest at the content of the expansive admixture of 5% and compared to non-mixture, 10% mixture of silica fume improved compressive strength about 32%. And in the result of the study to change the compaction load, the compressive strength increased from the load of 15kN, the void ratio decreased from the load of 0.8kN, the coefficient of permeability decreased from the load 35kN, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.8
• /
• pp.4815-4820
• /
• 2014

As semiconductor chips are on a small scale, large content and high integratation, it is essential to develop the device of pick and place at the system of the semiconductor test handler to ensure its high precision and durability. In this study, inspection equipment frame model of a semiconductor test handler picker was investigated by vibration analysis with the property of the natural frequency and harmonic response. As 3 kinds of analysis case models, the device of pick and place was located at the left side (Case 1), the center (Case 2) and the right side (Case 3) of the upper guideline. The range of natural frequencies until the 6th order on this frame model ranges from 80Hz to 500Hz. As the analysis of the harmonic response when the frame is resonant, Case 2 showed the maximum equivalent stress of 52.802 MPa more than Cases 1 or 3. Case 2 was the most intensive among the three cases. Using the analysis result of this study, the design of the frame model, which can be applied to the safe working environment of the system is believed to be possible.

• Journal of the Korean Geotechnical Society
• /
• v.27 no.12
• /
• pp.17-25
• /
• 2011

A fabric of soil media may change due to certain factors such as dissolution of soluble particles, desiccation, and cementation. The fabric changes affect the mechanical behavior of soils. The purpose of this study is to investigate the effects of geo-material dissolution on shear strength. Experiments and numerical simulations are carried out by using a conventional direct shear and the discrete element method. The dissolution specimens are prepared with different volumetric salt fraction in sand soils. The dissolution of the specimens is implemented by saturating the salt-sand mixtures at different confining stresses in the experimental study or reducing the sizes of soluble particles in the numerical simulations. Experimental results show that the angle of shearing resistance decreases with the increase in the soluble particle content and the shearing behavior changes from dilative to contractive behavior. The numerical simulations exhibit that macro-behavior matches well with the experimental results. From the microscopic point of view, the particle dissolution produces a new fabric with the increase of local void, the reduction of contact number, the increase of shear contact forces, and the anisotropy of contact force chains compared with the initial fabric. The shearing behavior of the mixture after the particle dissolution is attributed to the above micro-behavior changes. This study demonstrates that the reduction of shearing resistance of geo-material dissolution should be considered during the design and construction of the foundation and earth-structures.