• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.252-261
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• 2003

Although the young spike of barley (Hordeum vulgare L.) or wheat (Triticum aestivum L.) is known as the most susceptible part to spring cold injury, the risk of cold injury is apt to be ignored in most breeding program due to the importance of early maturity. Based on these aspects, the types and inducing time, temperature conditions for induction and effects of cold injury on growth and yield in this study were investigated under greenhouse and field conditions through three years (1997-1999). In natural condition, low temperature around -2.4∼$-10.2^{\circ}C$ caused the death of plant. Several cold injury types such as partial degeneration of spike, partial discoloration of leaf, spike and awn, discoloration of culm and white spike were observed at low temperature around $-3.1^{\circ}C$. Low temperature around -2.4∼$-8.6^{\circ}C$ and 1.3-$7.6^{\circ}C$ caused degeneration and sterility of spike, respectively. Most materials were prepared to the spikelet foundation stage, spikelet differentiation stage, development stage of flower organ, booting stage and heading stage, which were known having risk for cold injury in field condition. Although most of the controlled stages were sensitive to the induced low temperature, booting stage was the most sensitive stage for cold injury. All of growth stages which were treated-heading stage, booting stage, development stage of flower organ, spikelet differentiation stage, spikelet foundation stage-were responded to low temperature treatment but the symptoms revealed were very specific according to the growth stages. Ears of plant in heading stage were discolored to white. Ears of plant in booting stage were degenerated in all or part of one. Plants in spikelet differentiation stage were sterile in all or part of one. When tried to detect the specific differences between normal and cold injured plants in appearance, spike length, distance between spike and flag leaf and the first internode length could be the critical points for occurrence of spike death caused by cold injury. In barley, the elongation of spike was stopped on 3.2cm after occurrence of spike degeneration, 4.7cm after occurrence of partial degeneration of spike, 5.0cm after occurrence of white spike. In wheat, it was stopped on 1.6cm after occurrence of stem death, 3.3cm after occurrence of spike degeneration, 8.3cm after occurrence of partial degeneration of spike, 8.1cm after occurrence of white spike, 7.5cm after partial discoloration of leaf and 9.3cm after partial discoloration of spike. The obtained results from low temperature treatment induced in growth chamber were similar to the field experiment, Beacuse the death of spikes was more when low temperature was treated two times than one times, the temperature should be upgrade to -3$^{\circ}C$ in order to get the same condition with field test.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.3
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• pp.174-182
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• 2011

The present study evaluated the major lead sources in a steel metallurgy industrialized city by measuring lead isotopes/lead concentrations of ambient air and potential sources in an industrial area and residential areas according to relative distance. The quality control program obtained during the measurement procedure for lead isotopes and concentrations exhibited $0.5ng/m^3$ for method detection limit, more than 90% for recoveries of standard particulate matters, and lower than 0.2% for reproducibility errors of four lead isotopes ($^{204}Pb$, $^{206}Pb$, $^{207}Pb$, $^{208}Pb$). For all three lead isotope ratios ($^{206}Pb/^{204}Pb$, $^{207}Pb/^{206}Pb$, $^{208}Pb/^{206}Pb$), the ratios were obtained in the industrial area were closer to nearby residential area than those of a residential area far away from the industrial area, thereby suggesting that lead sources were more similar each other in the industrial and nearby residential area. Furthermore, for both summer and winter seasons ambient lead concentrations were more than four times higher in the industrial area than in the residential areas and in turn, they were higher in the nearby residential area compared with the far-away residential area. As a result, it was suggested that lead emitted from the industrial area would influence more the ambient lead in the nearby residential area than the far-away residential area. Both slag and traffic emissions are likely to be major lead sources in the industrial and nearby residential areas, since their three lead isotope ratios ($^{206}Pb/^{204}Pb$, $^{207}Pb/^{206}Pb$, $^{208}Pb/^{206}Pb$) were similar to the ratios obtained from ambient air of these two areas. In addition, the lead isotope ratios revealed different pattern between seasons, and the ambient lead concentrations were higher for winter than for summer.

• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.649-658
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• 2003

Early introducing the ducks into the paddy field involves a variety of environmental changes such as new surroundings and contact with water, so that some free-ranged ducks show behavioral and physiological changes indicative of stress or die from not adapted for new circumstances. Moreover, the free-ranged ducks was tread on the rice plant, and required a great deal of labor and time for captured the ducks after finishing the introducing. The aim of the present study was to examine the effect of accustoming and imprinting of duckling on behavior patterns, body weight gain and yield of the rice plant in paddy fields. Three paddy plots were used as control (no imprinting and no contact with people), taming (imprinting and regular handling) and roughness (handling roughly and strike terror to ducks) plots. Right after introducing the ducks into the paddy field, eating and moving behaviour of taming plot ducks tended to be longer time spend than that of other treatments. However, eating and moving time tended to be longer in the control than that of other two treatments on the 2 weeks after. Flighting distance was not showed in the free-ranging period taming plot, but the control plot was significantly (P<0.05) longer than the roughness plot. The captured time of free-ranged ducks tended to be shorter in the order of taming, control and roughness plots. Body weight gains was not significant. The number of rice plants damaged by free-ranging ducks in the taming plot were significantly (P<0.05) less than that in the control plot, but the yield and yield components of the rice plant were not differ among 3 treatments. These results indicated that the imprinting or regular handling and related treatments of duckling was reducing badly damage of rice plants, captured time and labor of free-ranged ducks in paddy field, although the working behavior of ducks and yield ability of the rice plants were not affected.

• Korean Journal of Environmental Agriculture
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• v.25 no.1
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• pp.7-13
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• 2006

Plastichouse cultivation for crops and vegetables in the winter has been widely popularized in Korea. In the vinylhouse Ultraviolet B penetration is lower than in the field, and so some problems, as plant overgrowth and outbreak of disease, occurred frequently. The effect of artificial supplement ultraviolet B $(UV-B:280{\sim}320nm)$ radiation on the physiological responses and yield of perilla (perilla frutescens) was investigated UV-B ray was radiated on perilla with the 10th leaf stage at the distance of 90, 120 and 150 cm from the plant canopy for 30 days after planting in the vinylhouse. The production of fresh perilla leaves was high in the order of plastic house, ambient+50% of supplemental UV-B, ambient ambient+100% of supplemental UV-B. Enhanced UV-B radiation affected the intensity of thirty-three proteins in 2-dimensional electrophoretic analysis of proteins and ten proteins out of them seemed to be responsive to UV-B : a protein was, ATP synthase CF1 alpha chain, down regulated and nine proteins (Chlorophyll a/b bindng protein type I, Chlorophyll a/b binding protein type II precursor, Photosystem I P700 chlorophyll a apoprotein A2, DNA recombination and repair protein recF, Galactinol synthase, S-adenosyl-L-methionine, Heat shock protein 21, Calcium-dependent protein kinase(CDPK)-like, Catalase) were up-regulated.

• The Journal of Engineering Geology
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• v.28 no.3
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• pp.411-429
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• 2018

Daeyoung mine (also called "Daema mine") produced gold and silver from mainly gold- and silver-bearing quartz veins. The mine tailings are a waste hazard, but most of the tailings were swept away or dispersed throughout the area around the mine long before the tailing dump areas were transformed into agricultural land. Soil liner and protection facilities, such as retaining walls, were constructed in the mine area to prevent the loss of tailings. The content of the tailings is 3,424.41~3,803.61 mg/kg, which exceeds the safety standard by a factor of 45. In addition, contamination was detected near agricultural areas and in the sediments in downstream drainage channels. A high level of As contamination was concentrated near the waste tailings yard; comparaable levels were detected in agricultural areas close to streams that ran through the waste dump yard, whereas the levels were much lower in areas far from the streams. The contamination in stream sediments showed a gradual decrease with distance from the mine waste yard. Based on these contamination patterns, we concluded that there are two main paths that affect the spread of contaminants: (1) loss of mine waste, and (2) the introduction of mine waste into agricultural areas by floods after transportation by streams. The agricultural areas contaminated by mass inflow of mine waste can act as contamination sources themselves, affecting other agricultural areas through the diffusion of contaminants. At present, although the measured effect in minimal, sediments in streams are contaminated by exposed mine waste and surface liners. It is possible for contaminants to diffuse or spread into nearby areas if heavy elements trapped in soil grains in contaminated agricultural areas leach out as soil solution or contaminant particles during diffusion into the water supply.

• The Journal of Korean Society for Radiation Therapy
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• v.22 no.1
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• pp.53-60
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• 2010

Purpose: We try to calculate EDW-factor easily with the formula applies essential data of EDW-factor and evaluate the validity through a measurement. Materials and Methods: We used the given value of GSTT (Golden Segmented Treatment Table) for the calculation of the EDW-factor. As to the experimental device, 0.6 cc farmer-type ion-chamber, an electrometer and water- phantom were used. A measurement was made at the maximum dose depth of the photon beam energy 6 MV and 15 MV under the condition that SSD (Source to Surface Distance) was 100 cm. The angle of the EDW (Enhanced Dynamic Wedge) which we use in an experiment was 60 degree, 30 degree, 20 degree in the Y1-OUT direction. We used Eclipse planning system (Varian, USA) as RTP system and the EDW-factor was calculated about all fields and EDW direction. In order to show the EDW-factor feature, a measurement was made at the selected field that verify the influence of the dependability about X, Y jaw and off-axis field. Results: When we change the Y1 field, it influence on the EDW-Factor and measured value. But the error between measured values and calculated values was less than 1%. The experimental result indicated the tendency that the error of the result of calculation and measured value becomes smaller as the EDW angle become smaller whether the calculation point (measurement point) and iso-center are same or not. The influence of the field size and energy did not show up. We simulated with the same condition using the RTP system. And we found that it makes no difference between the MU which is calculated manually by applying the EDW-Factor obtained from the commercial program and the value which is calculated by using RTP system. Conclusion: We excluded fitting value from well-known EDW-Factor formula and calculated EDW-factor with the formula applies essential data of EDW-factor only. As a result, there are no significant difference between the measured value and calculated value and it showed errors less than 1%. Also, we implemented the commercial program to calculate EDW-Factor conveniently without measure a factor on each field.

• The Journal of Korean Society for Radiation Therapy
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• v.22 no.1
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• pp.47-51
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• 2010

Purpose: In the treatment of high-energy protons Air gap (the distance between the patient and the exit Beam) Lateral Penumbra of the changes to the increase in the radiation fields can form unnecessary and Increase the maximum dose at the site of treatment and reduced the minimum dose homogeneity of dose distributions can decline. Air gap due to this change in dose distribution compared to investigate studied. Materials and Methods: Received proton therapy at our institution Lung, Liver patients were selected and the size of six other Air gap in Field A and Field B 2, 4, 6, 8, 10 cm Proton external beam planning system by setting up a treatment plan established. Air gap according to the Lateral Penumbra area and DVH (Dose Volume Histogram) to compare the maximum dose and minimum dose of PCTV areas were compared. In addition, the dose homogeneity within PCTV Homogeneity index to know the value and compared. Results: Air gap (2, 4, 6, 8, 10 cm) at each change in field size were analyzed according to the Lateral Penumbra region Field A Change in the Air gap 2~10 cm by 1.36~1.75 cm, the average continuously increased about 28.7% and Field B Change in the Air gap 2~10 cm by 1.36~1.75 cm, the average continuously increased about 31.6%. The result of DVH analysis for relative dose of the maximum dose According to Air gap 2~10 cm is the mean average of 110.3% from 108.1% to a sustained increased by approximately 2.03% and The average relative dose of minimum dose is the mean average of 93.9% percent to 90.8 percent from the continuous decrease of about 3.31 percent. The result of Homogeneity index value to the according to Air gap 2~10 cm is the 2-fold increase from 1.09 to 2.6. Conclusion: In proton therapy case, we can see the increasing of lateral penumbra area when airgap getting increase. And increasing of Dmax and decreasing Dmin in the field are making increase homogeneity index, So we can realize there are not so good homogeneity in the PCTV. Therefore we should try to minimize air gap in proton therapy case.

• The Journal of Korean Society for Radiation Therapy
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• v.24 no.2
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• pp.61-66
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• 2012

Purpose: The purpose of this study is to compare plans prescribed to point A with these prescribed to point H recommended by ABS (American Brachytherapy Society) in high dose rate intracavitary brachytherapy for cervical carcinoma. Materials and Methods: This study selected 103 patients who received HDR (High Dose Rate) brachytherapy using tandem and ovoids from March 2010 to January 2012. Point A, bladder point, and rectal point conform with Manchester System. Point H conforms with ABS recommendation. Also Sigmoid colon point, and vagina point were established arbitrarily. We examined distance between point A and point H. The percent dose at point A was calculated when 100% dose was prescribed to point H. Additionally, the percent dose at each reference points when dose is prescribed to point H and point A were calculated. Results: The relative dose at point A was lower when point H was located inferior to point A. The relative doses at bladder, rectal, sigmoid colon, and vagina points were higher when point H was located superior to point A, and lower when point H was located inferior to point A. Conclusion: This study found out that as point H got located much superior to point A, the absorbed dose of surrounding normal organs became higher, and as point H got located much inferior to point A, the absorbed dose of surrounding normal organs became lower. This differences dose not seem to affect the treatment. However, we suggest this new point is worth being considered for the treatment of HDR if dose distribution and absorbed dose at normal organs have large differences between prescribed to point A and H.

• The Journal of Korean Society for Radiation Therapy
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• v.24 no.2
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• pp.183-188
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• 2012

Purpose: The concern of improving the quality of life and reducing side effects related to cancer treatment has been a subject of interest in recent years with advances in cancer treatment techniques and increasing survival time. This study is an analysis of differing scattered dose to the contralateral breast using common different treatment techniques. Materials and Methods: Eclipse 10.0 (Varian, USA) based $30^{\circ}$ EDW (Enhanced dynamic wedge) plan, $15^{\circ}$ wedge plan, $30^{\circ}$ wedge plan, Open beam plan, FiF (field in field) plan were established using CT image of breast phantom which in our hospital. Each treatment plan were designed to exposure 400 cGy using CL-6EX (VARIAN, USA) and we measured scattered dose at 1 cm, 3 cm, 5 cm, 9 cm away from medial side of the phantom at 1 cm depth using ionization chamber (FC 65G, IBA). We carried out measurement by separating effect of medial tangential field and lateral tangential field and analyze. Results: The evaluation of scattered dose to contralateral breast, $30^{\circ}$ EDW plan, $15^{\circ}$ wedge plan, $30^{\circ}$ wedge plan, Open beam plan, FIF plan showed 6.55%, 4.72%, 2.79%, 2.33%, 1.87% about prescription dose of each treatment plan. The result of scattered dose measurement by separating effect of medial tangential field and lateral tangential field results were 4.94%, 3.33%, 1.55%, 1.17%, 0.77% about prescription dose at medial tangential field and 1.61%, 1.40%, 1.24%, 1.16%, 1.10% at lateral tangential field along with measured distance. Conclusion: In our experiment, FiF treatment technique generates minimum of scattered dose to contralateral breast which come from mainly phantom scatter factor. Whereas $30^{\circ}$ wedge plan generates maximum of scattered doses to contralateral breast and 3.3% of them was scattered from gantry head. The description of treatment planning system showed a loss of precision for a relatively low scatter dose region. Scattered dose out of Treatment radiation field is relatively lower than prescription dose but, in decision of radiation therapy, it cannot be ignored that doses to contralateral breast are related with probability of secondary cancer.

• The Journal of Korean Society for Radiation Therapy
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• v.24 no.2
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• pp.149-155
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• 2012

Purpose: Long Extension (LE) is used in proton therapy for lung and abdomen. However, it has limitations in surface area, produces collision in posterior oblique beam which creates limitations in various gantry angles in planning therapy and increases air gap (distance between patient and compensator). Therefore, this study investigates the usability of manufactured Rounded Extension (RE) in comparison to LE to use the most suitable extension in proton therapy. Materials and Methods: To compare structural features of LE and RE. This study investigated usable gantry angle for snout sizes 100, 180 and 250 and CT scanned Humanoid phantom. And it compared the air gap in posterior oblique direction. Results: The structural features of two extensions are as follow. Because of the existence of supporting bar, the width of LE was 40 cm and RE was 50 cm. Result of the investigation of usable gantry angle for snout sizes 100, 180 and 250 are as follow. LE is ${\pm}36$ (average) at 180 degree and RE is ${\pm}70$ (average). And also, the air gap of RE is decreased by 11.3 cm in average at the same gantry angle. Conclusion: Manufactured RE for proton therapy has several benefits than LE. Its therapy surface area is wider and range of usable gantry angle is also wider. Also, the air gap at the posterior oblique beam has decreased. Therefore the usability of RE in proton therapy of lung and abdomen will be increased compared to LE. However, the air gap of proton therapy at the lateral direction may be increased, so there may be need for make up to decrease air gap at the lateral direction in the future.