• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.130-137
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• 2012

This study has conducted to develop new gabion wall systems with vegetation base materials for stream bank stability and rapid rehabilitation. Vegetation base materials are primarily compounded with fine soil, organic composts and peat moss as plant fibers, a water retainer and a soil improver. Normally gabion wall systems resist the lateral earth pressures or stream power by their own weight. Therefore, fill material must have suitable weight, compressive strength and durability to resist the loading, as well as the effects of water and weathering. In this project, 100 to 200-mm clean, hard stones are basically specified, and about 50-mm rubbles are also used. Test application of new gabion wall system carried out in the stream bank of a small stream in the Gwangreung experimental forest, belonging to Korea Forest Research Institute (KFRI) in December 16th, 2006. As a result of the analysis of hydraulic stability of new gabion wall system, gabion wall system has highest threshold shear stress when the gabion wall covered by vegetation. New gabion wall system is highly resistant to sliding and overturning because safety coefficients exceed 1.5. As a result of term of slope stability analysis of new gabion wall system by Bishop and Fellenius methods, stability of stream bank was highly increased after the construction of gabion wall. Therefore, new gabion wall system is effective to stabilize unstable stream bank.

• The Korean Journal of Mycology
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• v.45 no.1
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• pp.74-82
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• 2017

Lisianthus (Eustoma grandiflorum) is a flowering ornamental plant used widely in Korea. In 2015, wilting, damping-off, stunting, and root rot symptoms were observed in lisianthus plants of Yeoju and Gimhae, Korea. Affected seedlings appeared yellow and showed poor development of root systems in the field and in nursery boxes. Furthermore, affected plants were yellow, stunted, and died at approximately 2-3 months after transplanting. Fusarium species were consistently isolated from the basal stems of diseased plants. Nine isolates were identified as Fusarium solani based on morphological characteristics. Macroconidia of isolates were relatively wide, straight-to-slightly curved, and microconidia formed in false heads on long monophialides. Abundant chlamydospores were produced at the middle or tips of hyphae. To confirm this identification, a molecular analysis of the translation elongation factor 1 alpha (TEF) and RNA polymerase II subunit (RPB2) genes was conducted. The sequences of TEF and RPB2 showed 99.2-99.9% and 98.0-98.1% similarity, respectively, to those of reference F. solani strains in NCBI GenBank. Pathogenicity was tested using root dipping inoculation of healthy lisianthus seedlings. Symptoms were observed within 7 days of inoculation only in inoculated plants. This is the first report of F. solani causing Fusarium root rot on lisianthus in Korea.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.1
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• pp.7-10
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• 2013

A packaging system integrated in primary and secondary packages to deliver consumers fresh peach in the produce supply chain was designed and its effectiveness on quality preservation was tested. The master packaging system was designed to contain 6 individual polypropylene film (PP, $30{\mu}m$ thickness) packages of 300 g peach fruit inside $35{\mu}m$ thick low density polyethylene (LDPE) bag located in a corrugated paperboard box. As a variable to attain the desired package atmosphere around the fruit during cold storage and subsequent retail display at higher temperature, different numbers (1, 3 and 7) of microperforations in $59{\mu}m$ diameter were tested on the individual PP packages. As control treatment, six fruits were placed without wrapping in a corrugated paperboard box. During the storage at $5^{\circ}C$, the control and individual packages were periodically separated from the box or master package, moved to the simulated retail shelf conditions of $20^{\circ}C$ and then stored for 3 more days with package atmosphere and fruit quality being measured. The package with 7 microperforations was the best in the ability to attain beneficial MA of 6~10% $O_2$ and 11~19% $CO_2$ around the fruit during the chilled storage at $5^{\circ}C$ and simulated retail display at $20^{\circ}C$. Packages with smaller number of microperforations resulted in anaerobic atmosphere at the low temperature storage and/or the subsequent high temperature display. Compared to control, all the treatments with master packaging system gave better retention of fruit firmness with significantly less weight loss.

• Radiation Oncology Journal
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• v.19 no.3
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• pp.293-299
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• 2001

Prupose : LiF TLD has a problem to be used in vivo dosimetry because of the toxic property of LiF. The aim of this study is to develop new dosimeter with LiF TLD to be used in vivo dosimetry. Materials and methods : We designed and manufactured the teflon box(here after TLD holder) to put TLD in. The external size of TLD holder is $4\times4\times1\;mm^3$ To estimate the effect of TLD holder on TLD response for radiation, the linearity of TLD response to nominal dose were measured for TLD in TLD holder. Measurement were peformed in the 10 MV x-ray beam with LiF TLD using a solid water phantom at SSD of 100 cm. Percent Depth Dose (PDD) and Tissue-Maximum Ratio (TMR) with varying phantom thickness on TLD were measured to find the effect of TLD holder on the dose coefficient used for dose calculation in radiation therapy. Results : The linearity of response of TLD in TLD holder to the nominal dose was improved than TLD only used as dosimeter And in various measurement conditions, it makes a marginnal difference between TLD in TLD holder and TLD only in their responses. Conclusion : It was proven that the TLD in TLD holder as a new dosimetry could be used in vivo dosimetry.

• Current Research on Agriculture and Life Sciences
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• v.2
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• pp.29-33
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• 1984

From June 28th to July 17th in 1985, this study was performed to obtain the information of the fresh corn forage production through the spraying hydrophonics in summer. The experiments were conducted in vinyl house on Kyungpook University's Experimental Station. The results obtained were as follows: It was suggested that the treatment of soaking for 24 hrs and followed by the pretreatment for 48 hrs was better than other treatments. Seed cost for the production of 1 kg fresh forage was the most inexpensive at the seeding rate of 450 g per $30{\times}60cm$ tray than other seeding rates. Application of 1000 times diluted Hyponex solution (1000X Hyponex) or 300 times diluted Yogen solution (300X Yogen) one time per day resulted in the heavier fresh weight than the other treatments. Treatments of 300X Yogen and 500X Yogen gave the better fresh weight in one application per two days and per three days, respectively. But, this method was not useful in summer because the lowest seed cost for the production 1kg fresh forage was 73Won, and collection of the fresh forage from the mountain range was easy.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.11
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• pp.105-114
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• 2015

This paper proposes methods to remove background area and segment region of interest (ROI) in chest X-ray images. Conventional algorithms to improve detail or contrast of images normally utilize brightness and frequency information. If we apply such algorithms to the entire images, we cannot obtain reliable visual quality due to unnecessary information such as background area. So, we propose two effective algorithms to remove background and segment ROI from the input X-ray images. First, the background removal algorithm analyzes the histogram distribution of the input X-ray image. Next, the initial background is estimated by a proper thresholding on histogram domain, and it is removed. Finally, the body contour or background area is refined by using a popular guided filter. On the other hand, the ROI, i.e., lung segmentation algorithm first determines an initial bounding box using the lung's inherent location information. Next, the main intensity value of the lung is computed by vertical cumulative sum within the initial bounding box. Then, probable outliers are removed by using a specific labeling and the pre-determined background information. Finally, a bounding box including lung is obtained. Simulation results show that the proposed background removal and ROI segmentation algorithms outperform the previous works.

• Journal of Radiation Protection and Research
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• v.13 no.2
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• pp.9-20
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• 1988

In order to quantify the contribution of cosmic-ray ionizing component to the dose given by natural background radiation, a series of measurement has been carried out using LiF TLDs for about one and a half years on quarterly basis. Three different types of LiF TLDs namely, chips and PTFE based disks of $^{7}LiF$, and the same disks of $^{6}LiF$ for identifying possible contribution of neutron component were used. Measurements were made by placing badge-incased TLDs in a lead castle of 10 to 15cm thick installed in a room on the third floor of a four-story building in CNU Daedeok campus for 5 cycles of 90 days. For comparison a series of spectrometric study was also performed for the energy region over 3MeV using a 3'${\phi}\;{\times}\;3$'NaI(Tl) scintillation detector in association with an MCA of 1024 channels, and it was found that the data obtained by the TLDs placed in the lead castle indicate 75% of the dose given by outdoor cosmic-ray component. The results obtained by the TLDs through correction for shielding loss show that the outdoor dose contribution of ionizing component of cosmic rays at this campus is $34.3{\pm}1.1nGy/h$ which satisfactorily agrees with that expected for our particular location of measurement.

• The Journal of the Convergence on Culture Technology
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• v.5 no.4
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• pp.387-394
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• 2019

In this study, in order to evaluate the damage and deterioration of the track components of sleeper floating track (STEDEF), the field samples(specimens) were taken from the serviced line over 20 years old, and the track components were visually inspected, and investigated by laboratory tests and finite element analysis. As a result of visual inspection, the damage of the rail pad and fastener was slight, but the rubber boot was worn and torn at the edges of bottom. The resilience pads were clearly examined for thickness reduction and fatigue hardening layer. As a result of spring stiffness test of rail pad and resilience pad, the deterioration of rail pad was insignificant, but the deterioration of resilience pad exceeded design standard value. Therefore resilience pad was directly affected by train passing tonnage. As a result of comparing the deterioration state of the field sample and the numerical analysis result, the stress and displacement concentration position of the finite element model and the damage position of the field sample were coincident.

• Food Science and Preservation
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• v.15 no.5
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• pp.630-634
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• 2008

The effect of packaging methods on the quality characteristics of leaf lettuces was studied during storage at low temperature. Using five commercial packaging types: non-perforated PP (polypropylene) film bags, PP film roll, perforated PP film bags, PET (polyethyleneterephthalate) trays, and micro-perforated LDPE film bags, changes in color, respiration rate, and weight loss of leaf lettuces were investigated. Packaging in non-perforated PP film bags minimized color change and weight loss during storage. The leaf lettuces packaged in non-perforated PP film bags, among the five packaging choices, showed good external appearance and offered the greatest sale potential in the domestic market. However, there were no clear differences in the respiration rates of lettuces packed in various ways. The PET tray afforded very good protection of leaf lettuces from physical damage. The results indicate that the marketability of lettuces may be directly affected by the packaging modes employed, and that the optimal packaging may be non-perforated PP film bags; these keep lettuces fresh during low-temperature storage.

• Food Science and Preservation
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• v.17 no.5
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• pp.581-585
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• 2010

The effects of plastic container vent ratio on fruit quality during strawberry precooling and storage were analyzed. Plastic containers ($520mm{\times}355mm{\times}182mm$) were manufactured with bottom and side vents at areal ratios of 5%, 10%, 15% and 20%. Fruit was loaded at a volume ratio of 80% prior to pressure cooling and storage at $5^{\circ}C$. The internal fruit temperature was $18^{\circ}C$ and the times taken to attain $2^{\circ}C$ after precooling were 1 hour 9 minutes, 1 hour 13 minutes, 2 hours 2 minutes, and 2 hours 51 minutes at vent ratios of 20%, 15%, 10%, and 5%, respectively. To mimic the current distribution system, precooled strawberries were packaged in tray wrapping and stored at $5^{\circ}C$. Changes in weight, bruising, extent of decay, and firmness, were measured. Weight loss, bruising, and decay were highest at a vent ratio of 20%, lowest at a vent ratio of 15%, and moderate at vent ratios of 5% and 10%. No significant among-treatment difference in fruit firmness was evident.