• Korean Journal of Environment and Ecology
• /
• v.29 no.4
• /
• pp.590-598
• /
• 2015

Despite various control methods for pine wilt disease, the disease has been increasing at an alarming rate every year in Korea. Still there is a lack of research on the problems of the current methods used to curb the disease. One main method to control pine wilt disease is fumigation for eliminating the larva of the pine sawyer beetle (Monochamus alternatus) which is known as the vector insect for pine wilt disease. We surveyed and analyzed the amount of destroyed uninfected trees in the fumigated area by studying 32 survey plots ($100m^2$) in Miryang city. The destroyed trees' crown area was estimated by induced regression between root collar area and crown area of the remaining trees (coniferous tree: $R^2=57.4$, deciduous broad-leaved tree: $R^2=63.8$). According to the analysis results, the infected trees (cut trees) were 18.7% and cut trees which were not infected were 35.5% of the total tree population of the study area on the basis of total crown area. In case of pine trees, 8.4% of uninfected trees were cut off but 62% of uninfected deciduous broad-leaved trees including Quercus spp. were affected and damaged during the fumigation process. Since these broad-leaved trees dominate the sub-canopy layer of the forest, this indiscriminate interruption of broad-leaved trees has the adverse effect of depriving the public benefits such as shadow, a cooler weather, controlling humidity, etc.

• Journal of the Korean Institute of Gas
• /
• v.20 no.4
• /
• pp.33-43
• /
• 2016

Grinding, weld deposition, type A sleeve, type B sleeve, composite sleeve, hot tapping and clamp are used as the method to repair the buried pipelines in the United States, UK and Europe. In the event of defect to the pipeline, they have repaired the pipeline through the fitness-for-service assessments. In addition, they have guidelines for the possible repair methods to apply to each type of damage, which is occurred due to the 3rd party construction or corrosion. According to the KGS FS551, Safety Validation in Detail including ECDA(External Corrosion Direct Assessment) as one method of integrity management should be carried out for the old pipeline which supply natural gas as the middle pressure in Korea. Where a defect on the pipelines is found, on the result of Safety Validation in Detail, the pipelines should be repaired or replaced by new piping. However, there are no guidelines or regulations regarding the repair and reinforcement of pipeline, so that, cutting the damaged pipeline and replacing it as a segment of new pipe is the only way in Korea until now. We have suggested pipeline repair methods including type A, B sleeve, composite sleeve, after the survey of foreign repair method and standards including the method of United States and the United Kingdom, and after analysis of the results on pipeline repair test including type A, type B sleeve and composite sleeve.

• Journal of Korea Water Resources Association
• /
• v.45 no.7
• /
• pp.643-656
• /
• 2012

There has been an increase for the landslide areas and restoration expenses due, in large part, to the increased locally heavy rains caused by recent climate change as well as the reckless development. This study carried out a slope stability analysis by the application of distributed wetness index, using the GIS-based infinite slope stability model, which took the root cohesion effect into consideration, for part of Mt. Umyeon in Seoul, where landslide occurred in July 2011, in order to compensate the defects of existing analysis method, and subsequently compared its result with the case on the exploitation of lumped wetness index. In addition, this study estimated the distributed wetness index by methodology, applying three methods of specific catchment area calculation: single flow direction (SFD), multiple flow direction (MFD), and infinity flow direction (IFD), for catchment area, one of the variables of distributed wetness indices, and finally implemented a series of comparative analysis for slope stability by methodology. The simulation results showed that most unstable areas within the study site were dominantly located in cutting-area surroundings along with the residential area and the mountaintop and unstable areas of IFD and lumped wetness index method were similar while SFD and MFD provided smaller unstable areas than the two former methods.

• Journal of dental hygiene science
• /
• v.12 no.6
• /
• pp.566-571
• /
• 2012

Marginal and internal fit are very important factor for the clinical long-term success of fixed dental prostheses (FDPs). A variety of methods have been applied to the measuring marginal and internal fit of FDPs. The purpose of this study was to compare the marginal and internal fit of 2 different measuring methods silicone replica technique [SRT] and die cutting technique (DCT). SRT, the space between die and FDPs were filled with light-body silicone, then stabilized by medium-body silicone. DCT, the FDPs were cemented on definitive dies and embedded into epoxy. The silicone replicas and epoxies were sectioned mesio-distal and measured 4 locations (margin, rounded chamfer, axial, occlusal) and using a digital microscope at a magnification $\times$160. For the SRT the mean${\pm}$SDs fit (${\mu}m$) recorded were: margin $88.7{\pm}22.2$, rounded chamfer $90.6{\pm}25.0$, axial wall $61.5{\pm}21.8$, occlusal $134.9{\pm}30.8$. For the DCT the mean${\pm}$SDs fit (${\mu}m$) recorded were: margin $85.3{\pm}18.0$, rounded chamfer $85.4{\pm}24.7$, axial wall $62.0{\pm}21.3$, occlusal $131.7{\pm}30.5$. The mean${\pm}$SDs size (${\mu}m$) of SRT margin was $88.7{\pm}22.2$ and of DCT margin was $85.3{\pm}18.0$. There were no statistically significant difference (p<0.05) of the four parts between SRT and DCT. It is considered an appropriate case to use SRT at fit of FDPs.

• Food Science and Preservation
• /
• v.19 no.6
• /
• pp.849-857
• /
• 2012

This study was conducted to determine the effects of the pretreatment and infrared drying methods on the physicochemical properties and antioxidant activities of dried peaches. The pretreatment methods were the 30 min treatment of NaCl, vitamin C, and soluble Ca (1:5 w/v immersion ratio), and leaving them untreated before infrared drying at $55^{\circ}C$ for 20 hr. The moisture content was lower in the pre-treated group and was significantly lowest in the 0.3% NaCl. The titratable acidity and soluble solid content and acid ratio (SS/TA) were high for the vitamin C and soluble Ca groups. The browning degree and cutting strength of the dried peach were lower in the pre-treated group. The total sugar content in the 0.3% NaCl group was significantly higher than those in the vitamin C and soluble Ca groups. The Ca contents were more effective in the soluble Ca treated group and increased with higher Ca concentration. The sensory evaluation results indicated that the organoleptic scores for the overall preference were higher in the 0.1% vitamin C treated group. The phenolic compounds and ABTS radical scavenging ability were high for the 0.1% vitamin C and 0.1% soluble Ca treated groups. These results suggest that pretreatment affected the qualities of the dried peaches, showing that infrared drying can be applied to the production of high quality dried peach products.

• Journal of Korean Society of Forest Science
• /
• v.110 no.3
• /
• pp.295-307
• /
• 2021

This study proposed a field-applicable natural regeneration method using natural seeding to afforest a secondary growth forest after felling in Larix kaempferi plantations. In 2016, an experimental site was established usingseed-tree and clear-cutting methods in Gapyeong, Gyeonggi-do, South Korea. Characteristics of seed fructification and inflow in the natural regeneration site were analyzed along with an experimental site in Bonghwa, Gyeongsangbuk-do, which was established in 2014. As a result, the number of seeds per individual tree of V age class L. kaempferi was 690,340 seeds in a good year, with an estimated 13.8 million seeds per ha fruited in natural regeneration sites of L. kaempferi with 25 seed-trees per ha. Seed dispersal began in September and germination rates of seeds dispersed until November were greater than 40%. Reserved seed-tree sites showed the highest amount of seed inflow, followed by the seed-tree site and clear-cut site in descending order. The reserved seed-tree method performed better than other methods for evenly scattering seeds. Therefore, the timing of logging and seedbed generation for natural regeneration of L. kaempferi is estimated to be most effective before September when seeds are purposefully scattered using the reserved seed-tree method as an effective method for uniform seed supply.

• Sleep Medicine and Psychophysiology
• /
• v.29 no.1
• /
• pp.15-20
• /
• 2022

Objectives: Suicide is the major public mental health concerns all over the world. The comparison of suicide attempters and suicide completers could be the fundamental evidence for the suicide prevention. The aim of this study is to explore the differences between suicide attempters and suicide completers in terms of the stressors, suicide methods, and psychiatric diagnosis. Methods: Two types of secondary data were collected for the analyses. Data of the suicide attempters (n = 680) were gathered by intensive reviewing the medical records of Samsung Medical Center, Seoul, Republic of Korea. Data of suicide completers (n = 11,722) were collected by the psychological autopsy data which were gathered by Korean Foundation for Suicide Prevention. Suicidal methods, psychiatric disorders and stressors before suicidal attempt were compared between suicide attempter and completers. Results: Suicide completers were older and male predominant compared to suicidal attempt. Hanging or gas intoxication were more commonly used in the suicide completion, while wrist cutting or drug intoxication were more common in suicide attempters. All types of stressors were found to be high in suicide completers than suicide attempters. However, the proportion of economic and physical stress were greater in suicide completers, while the proportion of family stress were greater in suicide attempters. According to the recorded diagnoses, the rates of depressive disorders, sleep-wake disorders, substance-related disorders were higher in suicide completers, while the rates of anxiety disorders and trauma- and stressor-related disorders, bipolar and related disorders and somatic symptom disorders were higher in suicide attempters. However, after controlling the gender and age, there were no significant differences in diagnosis between suicide attempters and suicide completers. Conclusion: These findings implicate that suicide attempters and completers differed in suicide methods and type of stress. The results suggests that economic stressors, physical illness might raise the risk of suicide completion.

• Trans-
• /
• v.7
• /
• pp.103-121
• /
• 2019

In some documentary films, there are interviews, but in some other ones, there aren't any. As for the documentaries with interviews, the director uses talking heads to suggest their own arguments and to have audience agree. It is evident that interviews play a key role since they lead the story of a human-related documentary. Some directors prefer interviews where directors' questions and interviewees' answers are both heard. On the other hand, there a re directors who carry out the story just by using the answers from the interviewees. Then, it becomes crucial that we understand both of these styles and have new perspectives when watching documentary films. Ethics has always been considered one of the most important factors in documentaries and since they are believed to be "true," the influence documentaries have on the society is enormous. However, possibilities of exaggerating or manipulating the "truth" always exist. Therefore, it is important for the audience to identify the intentions of the director. As a matter of fact, there have been countless researches being done, but it is difficult to find studies that discuss the ways interviews are used in documentary films. The two different styles mentioned above do have huge differences in terms of directing methods. Thus, taking a look at differences from diverse angles will help us better understand the essentials of documentary films. This study will take examples from the interviews in Michael Moore's (2002), (2007) and observe how the flow of interviews can change when the voice of the director gets involved. There will also be a close examination of interviews in Kim Ilran and Hong Ji Yoo's (2011), and (2005) directed by Jim Butterworth, Aeron Lubarsky, and Lisa Sleeth, as well as Sebastian Junger and Tim Hetherington's (2010). By a careful review, use of dissolve, cross-cutting, and flashback will be analyzed to show how different editing techniques have an impact on subjective views of the director.

• Weed & Turfgrass Science
• /
• v.7 no.2
• /
• pp.140-147
• /
• 2018

In Korea, mowing the grass of a grave (Beolcho) is a very important event preceded by Chuseok (Korean thanks giving day) and Si-Hyang (annual ancestral feast). Because Beolcho usually takes place one or two weeks before Chuseok, the traffic accidents on roads are getting worse and safety accidents are getting more and more. Erroneous Beolcho methods can cause the soil to be exposed and cause the loss of soil or the low shoot density of graveyard grass or weed occurrence. Therefore, the dispersion of the Beolcho timing and the approprite method can be import issues. The present study assessed the effects of grass mowing timing and height before Chuseok on the growth of Zoysia japonica and Z. matrella. The mowing timing was evaluated at 1 week, 2 weeks, 3 weeks, and 4 weeks before Chuseok, and the mowing height differently according to the two type of grass. In Z. japonica, the faster mowing before Chuseok, the longer the plant height, and the coverage rate and shoot density were higher. In Z. matrella, the faster mowing, the longer the shoot length, but the coverage rate and shoot density did not show any difference or tendency. As compared to Z. japonica, the plant height of Z. matrella was kept short regardless of the time of mowing. In both grasses, the plant height was shortened when mowing was done at low cutting height, but the coverage rate and shoot density were decreased. In addition, it was shown that it is advantageous to maintain the shoot density of graveyard lawn by 40-50 mm or 30-40 mm cutting above the ground for Z. japonica or Z. matrella, respectively.

• Journal of Korean Ophthalmic Optics Society
• /
• v.18 no.3
• /
• pp.231-239
• /
• 2013

Purpose: To design and fabricate the auto pattern maker for the development. Methods: we got the necessary data, needed in design, by using CAD. Based on the these data, we fabricated the trial product for the development of the auto pattern maker. Results: The auto pattern maker were composed with combinations of many elements; pattern making assembly, control panel, frame attachment and prober unit. The pattern making assembly was comprised of the cutter, the pattern holder, pattern remover and silence cover which could minimize the sound during the cutting process. The control panel was designed to be connected and operated with the main printed circuit board. The prober could get the eye shape data by scanning of 1.8 degrees around the groove of the frame through the encoding data according to the address. After starting, scanning was carried out in two passes, i.e. one right-handed and one left-handed. Communication connector could send the eye shape data from auto pattern maker to outer system with the RS232C transmission system. By using the one-way analysis of variance, we got the error rate of cut pattern size for ${\Phi}22mm$, ${\Phi}55mm$ and ${\Phi}62mm$. Because F-value was 0.510 and p-value was 0.601, no statistically significant differences were found. Also, the mean cutting error of the auto pattern maker was 0.0274 mm. Conclusions: we could succeed in making the trial product by applying it to the development of the auto pattern maker. The role of this auto pattern maker is to find a exact required size of lens to fit the frame by measuring the frame. The acquired data are transferred to outer system for grinding and finishing with patternless process. Also, the trial product can produce pattern to fit the frame. Therefore, it was confidently expected that the optometrists could handily produce pattern to fit the frame with this trial product and dispense the ophthalmic lens because of its efficiency and convenience compared to the past.